To get the fixed endings, you just have to be negative and all to all of your interactions with him until the alley scene— you have to kiss him there. Then after he kidnaps you and progress the dialogue, you can unlock that ending(s). It's all about encouraging him to turn himself in the police, which he agrees to, in the end. Then you get to decide if you stay or leave by his side (it doesn't affect anything, only the ending.)