What's Reimu doing in the last panel?

Stopping Suika.

Oh, that's her foot... I wasn't sure if she was holding something up or not. Still, ~$200 for a mini Suika slave/doll/maid/whatever is tempting.

Alice's sign doubles the last panel's humor.

if thats 'mini-suika' couldn't suika just make them disappear?

kona said:
if thats 'mini-suika' couldn't suika just make them disappear?

She's probably too hammered to remember.

Since mini-Suika is part of her hair, she needs to collect it back to make it disappear; or she can tell it to come back to collect it. She probably remembered former, and latter failed as mini-Suika likely likes to take it easy as it's master...