In One Piece party there are two omakes in the backs of the volumes with Kid and Killer. I wish there was more xD But they’re great. The portrayal of their characters is a little interesting, though.
In the first one:
Killer: *slurp slurp slurp slurp*
Kid: “STOP IT!!!”
And the second:
Killer: “Water seven” *pyuuuuu…….* “And then… ‘KNOCK UP STREAM’”
Kid: “STOP IT!!”
Why do you think they decided to introduce souske and then relate him to rin with such a strong bound? I mean before everyone was"mmmm makoharu or rinharu?" But now the couples are formed...I mean it's pretty clear that if they will go with some gay stuff people will know who is going with who lol