Chara obeys and stands beneath the faucet. WHOOSH! A whole cascade surges down the ragdoll's body and it's so exhilarating. It reminds Chara of those cartoons they see sometimes of martial artists meditating under waterfalls. They've been run under the sink a few times before, but nothing memorable. This, on the other hand, is awesome. Maybe it has to do with Undyne being so strong; so strong she can run the faucet on her own. Maybe it has to do with the fact she's doing this for them out of friendship. Hell, let it be both.

Undyne made bathtime fun.