You need to have the good ending (MC faints) during Blake oil/massage minigame
Ive been replaying the scene sm and still don't know how to make the MC faints☹️, do you have to choose only Blake from the start of the story?
start from the less intrusive parts like feet, calves… try each of them a couple of times until Mc says is time to move on. Leave the inner thighs for the last part, dont be eager :p