But that's not an ending with the MC. Yes, it was kind of strange that Rena just kind of disappeared and we didn't get to know what happened to her, but she, Megan, and Melissa all had happy endings with the MC by making certain choices along the way and the same will surely happen here too.
The biggest difference I could see between AL and BaDIK is that all LIs, whether they're with the MC or not, will (hopefully) have some kind of good, happy ending. I know people are expecting the absolute worst for some or all characters because of AL, but I don't think DPC will do this lest he be labeled a one-trick pony, so I'm holding to an optimistic view that he won't fuck everybody up in some big, OTT way. It's also worth remembering the genre of movie he's basing this game on and the "good guy" characters generally tend to get good endings in those films and so too could the "good guy" characters in this game.