Spiral/Funny

Eyes randomly taking a packet of dried sardines out of his pocket.

Eyes: There are those kinds of days, too.
Kousuke: (thinking) ... Just what kind of days are "those days"?!

In chapter 39 (Yen Press translation):

Hiyono: Right now, Narumi-san is being held in music room number 6 on the 5th floor of wing C. (...)
Kousuke: ... Little Lady... How do you know that?
Hiyono: Fufufu... I figured this would happen, so I put a tracking device on Narumi-san...
Kousuke, Ryouko and Rio: (stare at her with a random background of cute fishies)

Hiyono: (coughs) I mean! Call it the the sixth sense of a girl in love.

The kitty ears.
Ayumu, upon being asked what's the name of "that cute girl with the braids", honestly, seriously thinks about it for 3 panels before admitting, completely deadpan, "I forgot."
Many of the manga 4-koma (bonus 4-panel gags). Especially Kanone and Eyes throwing knives.
In Alive, Kiyotaka is the FASTEST FROG IN THE WOOOOOOOORLD. And green is beautiful.
- And anything Imari does, really, especially when she takes the nunchuks out.
Whenever Kannone isn't busy being an absolute badass, he tends to be side-splittingly hilarious.