They are similar in that they are very silly, comedy first romcoms. The main difference I think is that there is very little to no drama around the fact that the MC is dating multiple people. Everybody just accepts that fact and moves on. It becomes a running joke in the manga when the MC introduces a new girlfriend. 100GF mainly uses the cast of girlfriends to drive the comedy rather than actual relationship stuff.
Is 100GF like Girlfriend, Girlfriend?
They are similar in that they are very silly, comedy first romcoms. The main difference I think is that there is very little to no drama around the fact that the MC is dating multiple people. Everybody just accepts that fact and moves on. It becomes a running joke in the manga when the MC introduces a new girlfriend. 100GF mainly uses the cast of girlfriends to drive the comedy rather than actual relationship stuff.