[Killua lifts an arm to guard against the little baby-ways attack, just as a precaution. he of course used gyo on instinct to Eevee's initiation, and ryu on his arm to block.

he frowns, looking a little confused. like an emitter's hatsu, or something...]

Yeah. I see it.

[it kind of reminds him of one of his grandfather's hatsu...]

I don't think it's exactly the same as Nen, but...

[he notices the—charge? what was it that Eevee did? if it was like a hatsu, maybe it was like Killua's, some condition that required a charge...]

I saw streams of what I guess was probably his aura come at me. That's a thing Emitter type Nen users do at home.

[...it makes Killua a little sad, to be reminded of Gon's Scissors.]