Sweet Family summary:

Moontak, a jobless man who has been living at his girlfriend's house for two years after being discharged from the military. At the club where he secretly visits, he learns the secret of his prospective sister-in-law, "Youngah," and received a secret proposal.I thought everything was a secret between the two of us. Did my girlfriend find out?What's the fate between the two families that get tangled up the more I try to solve it?"Young master... We're family now, so you're going to keep that secret, right?""