Since the Hooker is at the other player’s house and not at home, any attacks targeting the Hooker in the night will fail; however, if the person they’re sleeping over at is being attacked, then they both are attacked.
Choosing a player to sleep with is an immediate ability. From that point on, they will stay with that player for the rest of the night. The Hooker may also choose not to sleep with anybody.
The Hooker may not sleep with the same player two nights in a row.