[Killua gazes at Eevee with a tired look. did he really think no one would notice??

he glances back at Blue, eyes stuck on Eevee by their corners for a moment.]

Eevee...?

I guess you're right; I see an aura around him, like I do everyone. But seeing that aura at all means something, I guess—it's not like plants have that.

Though, now that you mention it, I don't think I've seen him ever do anything unusual. Headbutts, tackles...