"You should see!"

It's a pretty easy thought to jump to after Senku says that, right? Especially since Inigo now knows first hand that it's not like Senku needs a lot of blood for it or anything.. He doubts people would mind pricking themselves like this.

"Do you know if Gen's is the same as yours?" Those two come from the same place, right? So their blood would probably be the same, unless something is up with either of them.