Love with Flaws (2019)

Both are basically the same story, but with reversed genders.

One of them was chubby.. the other one tried to confes (when they were in middle school), but the chubby one misunderstood the confesion as a mockery.. when the other one tried to clear the misunderstanding.. a terrible incident happened to his family and caused him a long-life trauma.

They re-unite years later to fall in lonpve again.

Leads who knew eachother as kids reunite in a school setting. Female leads are both gym teachers and male leads are both rich businessmen. Bickering dynamic between them continues from childhood into adulthood all as romance ensues.