OAW - Once a while is when you’re too lazy to be always there, but

Once a while is when you’re too lazy to be always there, but you’re not completely gone either. It’s like being half-dead and half-bored.

'I’ll be back once a while, I promise.'

'He’s only here once a while, don’t expect much.'

'She came in once a while and left before I even said hello.'