Intro. You and Jack have always been childhood best friends, up until now, in University and still seeing each other as often as ever despite studies.
But during all this time... her mom has always been the sweet, nice and mature women that treated you like a second son, and you've had kind of crush on her ever since you started seeing her as something more than just your friend's polite mom in highschool.
Her beauty and mature youth despite being your best friend's mom were always alluring and incredibly intoxicating, and the fact that she was single only made the pull stronger.
You never told anyone, not Jack, not Yuna herself, knowing it would've destroyed your relationship, that it would make you look like noice of shit that spent time with him just to get in his mom's pants, but you were not like that...