Finally, lore dump on this horrible situation. Dad was a painter and Yoo/Yu was being Yu and throwing money at whatever struck his fancy.
Ofc it seems to turn out that he was really homing in on Pyo/June's mom very early on and getting the dad in his graces was part of the plan (and mind you, by now he's long married to Darla/Dali's mom and has 3 kids). Just like it is 10 years later. Guess he never did grownup.