Kei Enjyoji was born the illegitimate son of a yakuza boss.  Kei grew up not knowing any of his family aside from his mother, who died from an illness while he was in high school.  He was the president of the tea ceremony club and was generally introverted except when it came to Ran.  Ranmaru Samejima grew up with his grandfather and younger sister, and was the latest in a long line of kendo champions.  His grandfather owned a dojo and Ran worked very hard to become as good as his late mother.  Ran excelled at kendo and loved the competitive aspect of it, and his future in the sport looked very promising.  He became a rising champ in school and in tournaments, although he could never find a satisfactory sparring partner until he met Kei at school.  Kei was also talented at kendo, but he did not want to pursue it competitively or even join the club for it at school.  Since it allowed him an excuse to be around Ran, though, he agreed to practice with him.  Since Ran devoted his life to kendo, he did not have many friends.  Kei was the very first person he ever brought home from school, and they eventually shared their first kiss in Ran's family dojo.

Over the next few years, Kei and Ran became close friends and lovers.  Things were going very well for them until the day that Kei's mother passed away.  As he sat staring out the window into the rain, Ran came over and comforted him, telling him that he would always be there to protect him.  Neither of them could have realized just how soon Ran was going to have to live up to his promise, though.  As they were leaving the building, a car driven by a yakuza member sped up towards them as they were crossing the street, heading right for Kei.  When Ran saw what was going to happen, he pushed Kei out of the way and was hit by the car, his umbrella sent flying.  The car fled the scene and Kei was completely in shock at seeing his lover bleeding on the ground.  He cried in disbelief and clutched Ran to his chest while screaming his name.

Ran just barely survived the accident, and although he pulled through, the right side of his body was paralyzed.  It was hard enough to look ahead to his future once he learned of this news, but even harder when he learned that he would not be able to do kendo anymore.  Kei decided to stay by Ran's side always, not only because he loved him, but also because he felt responsible over what had happened.  It turned out that the car was driven by a member of a rival yakuza gang, and Kei, being a Sagano, was the primary target of the attack.  Ran did eventually regain the use of his arm and leg again, but it was going to be a very long time before he could even think about holding a sword again, if ever.  After he left the hospital, Ran moved in with Kei.

Things went relatively well for Kei and Ran as they settled into their everyday routines and adjusted to being roommates, until the day that Kai, Kei's younger half-brother entered the scene.  Kai was also a kendo champion and worshipped the ground that Ran walked on.  Needless to say, this did not go over well with Kei.  Over the course of the manga, Kei and Ran's love was put to the test numerous times.  From Ran suspecting Kei of cheating on him to Kei's kidnapping by a yakuza gang, they made it through many rough times together.  In volume 6, after Ran had helped rescue his lover, Kei proposed and the two exchanged their own vows right there in Kei's hospital room.  Once Kei was released from the hospital after recovering from his gunshot wound, the two went on a honeymoon to a hot spring resort.  It would have been very romantic if it weren't for the fact that two of the Sagano yakuza members came along for protection and even Kai decided to join them!  Kei and Ran still managed to have some quality time together on the trip before heading home so Ran could start working on his kendo once again.

One thing that was really interesting to watch as this series progressed was the growth of the characters, both individually and in their relationship.  One of the main turning points, to me at least, seemed to be when they exchanged rings.  At that point, Ran seemed to have made peace with the fact that he needed and wanted Kei in his future, despite what society and his family might think, and started focusing on what needed to be done to keep their happiness.  There was a scene in volume 9, where Ran was explaining to Kai that even though he and Kei were not married in the eyes of the law, to the two of them it was real, and as long as he was a productive member of society, no one could look down on him for his relationship with Kei.  I thought that was an interesting contrast to volume 3, where he was wondering how in the world they could stay together after college.  Kei also seemed to grow throughout the series, finding his own aspirations for his future, as well as doing as much as he could to provide for Ranmaru, both financially and emotionally.  I have never seen a character as supportive of their lover as Kei was.

The series seems to have reached it's conclusion in volume 11, and the final two volumes were really important to Kei and Ran's relationship.  In volume 10, Ran's grandfather decided to sell the apartment so Ran could move back home and eventually inherit the house and the dojo.  Ran also met his father, who turned out to be a really wonderful man, and he confided in him of his marriage to Kei.  It was through telling his father and gaining his acceptance that Ran found the courage to decide to tell his grandfather.  And although that confession was a little bit more dangerous (literally!) than they had planned, all was eventually well.  Kei and Ran both moved into Ran's family home together to begin the next chapter of their lives in the very room where Ran's parents had begun theirs.  I don't know if Kizuna will continue after volume 11, since everyone's stories were wrapped up so nicely, but I can only hope we will see more of these wonderful characters again in the future.

Kei and Ran are such a sweet couple.  They are already in a committed relationship, a marriage, even, and I imagine that they would continue to live out their lives together.  Every problem that they overcame together only made them stronger, and I think that their bond is unbreakable.  I'm not sure what their future would hold, but I can see them working through everything together.  I bet that Kei would open up the little shop that he wanted and Ran would continue to teach Kendo, and they would continue to dote on their little nephew, Takumi.

In book 6 of the manga, Kei was recuperating in the hospital from his gunshot wound.  Kei presented the matching ring he had bought Ran before his kidnapping and decided to propose to him right then and there.

Kei: "Please marry me. I, Kei Enjyoji, hereby swear to love Ranmaru Samejima for the rest of my life."

Ran: "That was it? That's how you propose?"

Kei: "Well, I planned a lot of lines, but they got all mixed up. I did take a few blows to the head."

Ran: "You could use a few more."

Kei: "Hey, I'm being serious here!"

Ran: "Two men... can't get married..."

Kei: "Well, maybe not legally... But I'm not gonna marry anyone but you. So just say yes. If you don't, I'll be a bachelor forever. Hey, I'm begging you. Marry me."

Ran: "Enjyoji... [cries] That's the... most awful proposal I've ever heard."

Kei: "Sorry. Ranmaru Samejima, do you swear to love Kei Enjyoji for the rest of your life? Say 'I do!'"

Ran: "I might as well... 'I do.'"

Kei: "What do you mean, 'might as well!?'"

Ran: "Like you said. I don't want to be a bachelor forever, right?"

Kei: "You jerk!"

Ran: "Back at you."

Kei: "What about our kiss!?"

Ran: "We might as well."

Kei: "Gee, thanks a lot." [they kiss]

Ran: "Enjyoji, I swear... I will love you forever."

~~~

As Ran prepared for his very first kendo tournament since the accident, he found himself a lot more nervous than he had expected.  Kei offers his support and words of encouragement to his lover.

Ran: "Enjyoji."

Kei: "Hmm?"

Ran: "I lied before.  My hands are shaking.  They didn't shake this badly the first time I ever competed in a tournament.  It's different from then.  It's not excitement from whether or not I'm going to win or lose.  It's a question of how far my hands and body will carry me.  How long will they last..."

Kei: "Come here.  I have a good luck charm for you."

Ran: "Sounds suspicious."

Kei: "Just get over here."  [holds both of Ran's hands]  "You really are shaking."  [kisses the palms of his hands]

Ran: "What..."

Kei: "It's fine.  Ran, you've gotten stronger.  Don't worry.  You can fight for sure.  You don't need to think about winning or losing.  Just enjoy the Kendo you love as much as you can.  Just know that I'm always looking at you."

Ran: "Yeah."  [thinking]  'That's right.  You'll be watching me.'