Hokuto no Ken Episode 25
Ko is captured by the Fang clan, who go back to Mamiya's village and execute him in front of everyone. As they drive off, Ko's body is taken back into the village. Kenshiro, Bat, Lin and Rei find out that Ko was actually Mamiya's brother, and the only family she had left. Finding the Fang clan's actions unforgivable, Kenshiro decides to go out and avenge Ko. However, he discovers that Rei has had the same idea, and has placed himself right in the middle of some Fangs.
Kenshiro jumps down and he and Rei find out that seem to have the same weakness -that of a woman's tears. Kemada is annoyed that the two are ignoring him and sends his men to attack, but Ken and Rei team up and destroy them all.
Soon Kemada is the only one left standing, and he cries that his father will go nuts if he finds out so many of his sons have been killed. Neither Ken or Rei care about his words, and Kemada is killed. Ken finds out why Rei is also after the man with seven scars -apparently, Rei's village had been attacked by bandits, and his sister was kidnapped. Just before he died, Rei's father told his son that the man who took Airi had seven scars on his chest. Back in the present, Ken and Rei return to the village, and Ken presents Mamiya with Ko's pendant, which Kemada had stolen earlier.
In the manga...
-The birthday cake stuff was never in the manga.
-Ko is never seen being captured in the manga. Also, the manga is a little different timing wise of this part of the story -the Fangs arrive with Ko immediately after Rei tells Ken he wants to kill the man with seven scars. In the anime, at least a few hours have passed between the end of the previous episode and the start of this one.
-Kemada makes his debut in the manga when he kills Ko, but in the anime, he was introduced early, back in this episode. Kemada is never named in the manga either.
-Kemada does not mention his father to Ken and Rei in the manga.
-Just before Rei explains to Ken about his past, he offers Ken a drink from his flask. This isn't in the anime.
-Whilst Rei explains his reasons for wanting to kill the man with seven scars to Ken in the manga, you never see the flashback scene with his family and the masked man. This was added for the anime.
-Also, the manga had an additional scene where Ken asks Rei what he would do if he found out Ken had seven scars on his chest -this scene was saved for the next episode of the anime.
-When Kenshiro flips over a Fang, his red shirt is missing, and you can see some of his scars. Good job Rei wasn't looking at him at the point!