i was kinda hoping that he'd have a special dialogue if you wear the most inappropriate outfit to the confrontation ... but sadly he just continued on with his speech as if everything was normal 😂
From what I can tell you need to max out Lily affinity by doing certain side missions along with picking up specific collectibles that increase the affinity bar. You'll know you picked up the right collectible if you see a diamond icon with her face on it that pops up along with a progression meter. Once you get to 100% the progression bar disappears and you can get the ending.