I've decided how the roll will happen, in the fairest way possible.

Everyone with a male student, choose a number between between 1 and 20 to be their bed number. It'll be a simple lottery, with a dice roll determining randomly which bed the message is in. Considering the size of the cast, there's a fair chance that no one will get, in fact, which means that Lotte will find it when she's doing her maid duties on the other day. (i.e.: the odds are stacked heavily against  Circe).

Anyway, your picks: [@Silver Carrot], [@Sync], [@floodtalon] and [@Awesomoman64].

Nothing more just than letting luck decide.