Bruce regularly has horrible nightmares that ruin his sleep. Clark can hear him tossing and turning and moaning all the way from Metropolis (he was just checking in on Bruce ;)) and wants to help him, somehow.

Bonus if he and Bruce aren't exactly friends yet (let alone more), so it's all really awkward and kind of antagonistic and Bruce is pissed off that Clark knows he sleeps badly and Clark is pissed off that Bruce doesn't want to accept any help.