DPC has said they won't have a harem in the game, but this is not a harem, not even a mini one, it's a throuple and such things exist in the real world so it's not as unrealistic as the multi-women harems that are present in so many other games.
Yes, they quite literally burned away the last potential throuple in AL, but that is not necessarily indicative of this one also not working out. It cannot be said that it's definitely not going to happen, and I guess the same can also be said of it happening, but a throuple ending is entirely possible at this stage and will all depend on how DPC wants to write it, but there's no reason why they can't make it work as
ename144 was saying.
The game is certainly dangling that carrot in front of us just like AL did, and to make this another no-win situation would be bad form just as it would be if they did it with any other LI.