After his experience in the hall of mirrors, Sephiroth is savvy enough (while sober at least) to avoid those rides where the attendants insist on partners. He hasn't been inside of the haunted house, but he notices the man stumbling away from it, apparently injured. Even in the dark, he can tell that that isn't human blood, but that isn't the important thing to him at the moment.

"Did something attack you?"

He isn't remotely alarmed; in fact, his interest is piqued by the possibility of something to fight. His skills are wasted on most of the 'challenges' the Ancient likes to set for them. Give him a little actual danger for once.