Sendoh's first episode has a scene where Takamura mistakes Sendo for Aoki in the showers, tried to grab him, and Sendo counterattacks by grabbing Takamura's cock. Ippo and the others's horrified reactions only made it even funnier.
And there's also the multiple date, when after making peace with Kumi Ippo finally gets to go out with her, but ends up terrified because of Mashiba's Big Brother Instinct: that episode is utterly hilarious from the beginning to the end.
Especially since out of the four Kamogawa boxers, AOKI is the only one who gets anywhere with his lady, who ends up becoming his girlfriend.
Thwe scene where both the cast and the viewers/readers find out makes it even better. Ippo, Takamura and Kimura arrive to the gym in time (and Takamura gets yelled at by Kamogawa for his... antics), but Aoki doesn't. The three are sure that he's had it worse and call him to his apartment to check on him. The one who answers the call? Tomiko, Aoki's date. The guys's faces are priceless.
The second beach training arc, from Takamura mistakenly grabbing Aoki's girlfriend down to the infamous bug incident - pure comedy gold. If you're into that.
Sendo, Saeki, Mashiba, Okita and Date arguing with each other over who's match with Ippo was the best, with Kumi of all people shutting them up.
Imae vs Aoki: Tomiko, Itagaki's dad and Takamura are sitting near each other in the audience. Takamura pokes fun at Aoki's performance and Itagaki's dad makes puns about it, which angers Tomiko, who smacks then both. Later on in the fight, there are times when Itagaki's dad makes an innocent comment or says something that has to do with the fight and Tomiko mistakes it for a pun and smacks him anyway.
How about when the gang wrote on Ippo's penis? Who does that?
For those unaware, a reporting crew comes to the gym and Ippo is asked to spar with their female reporter (much to the jealousy of the other guys). Considering he can't go full power (and even a light hit would probably be bad), he decides to aim for the body. He MISSES, and hits her BOOB. Cue nosebleed and all the guys teasing Ippo. And it only escalates from there...
The arm wrestling match. Takamura has the best troll faces!
The celebration victory at the beginning of Champion Road. From the return of the karaoke scene to the Kamogawa calling out Takamura, again.
After Itagaki's first victory, Ippo goes to have dinner at his house, and he gets to meet his family. Turns out they're a great family, but terrible comedians. While their puns are cringe-worthy, Ippo's reaction to them is hilarious.
Nanako vs. Kumi vs. Iimura. The winner? Ippo's mom.
Even funnier that Ippo was asleep from his match the whole time, and that Umezawa had to fill him in on what happened.
Umezawa: I guess... you could call it a draw...
When Ippo tries to learn more about Sendo through watching his matches on video. Too bad that the tape he chose, Takamura had taped half of it over with porn.
At the end of the tape, we're about to see Sendo's finishing move. Instead, the ending to the porn.
After the Sawamura and Makunouchi fight Kumi has a chat with Hiroko about Ippo and his dad. When they finish it becomes late and Kumi decides to leave.
Hiroko: Nonsense! I'll hail a cab for you!
Kumi: Oh, you don't have to!
Hiroko: (looks outside) No. There's a strange man waiting outside.
Sendo makes it to Miyata's gym to spar. At first, Miyata doesn't agree to it, until Sendo smacks him in the head. Miyata agrees, and asks Sendo if he brought any gloves. Which he uses to throw at his head when Sendo goes to search for another pair.
Even before that, when Sendo smacked Miyata, Ippo was about to run over to tell him off before being stopped by Itagaki.
After a discussion about Kimura's inability to get a girl, Aoki concludes it's because of a lolita complex when he found some anime merchandise hiding under his bed. He deflects it with a lame excuse by saying he has a girlfriend. No one but Ippo buys it.
After a brief discussion about Kimura's lack of a girlfriend, Aoki calls him. He says that he'll show them some other time, just as he walks past them holding a little girl's hand, surprising everyone in a big misunderstanding. The next chapter shows him coming out of a police station.
Sendo successfully grabbing and creating a legion of cats that follow him while he visits Ippo in Tokyo.
Chapters 943 and 944. Takamura gets into a bar fight with Sendo, Mashiba, Saeki, Okita and a drunk Date.