Webtoons 2

Guide verse with childhood friends, FL has like 1 brain cell and ML has liked her since middle school (they're 26 now).

I think ML regressed and wants to save the FL from marrying her fiance who will kill her in the future. However it's a bit messy because the FL used to like the ML for 19 years and then suddenly he's back saying he doesn't like her but they need to get married so she doesn't die...but doesn't explain any of this to the FL