Um, look, I hate harem endings, I mean I hate true harems. But, it's tolerable if the guy is a GOOD GUY, but I'd still dislike that character for how he loves. I would also hate the girls in that ending but in the end there's nothing you can do, and to a reader they may remain as someone whose character has failed in some way which made them accept such situation.
If it's actually a harem ending then this is one of the worst mangas I have read. I have wasted time.
SPOILER;
It's alright if he was a good guy but he became a piece of sht, he fcking cheated multiple times. He lied multiple times, he lied by omission multiple times. But, they still chose to be with him and even share him in the end? Fck this, I hate yanderes but I hope there was an alternative version where a yandere comes and ruins his life and makes the girls face reality.
;edit; Yes, it's actually harem ending. The chapter is literally just all of them doing it, I don't think the author even loved what she wrote because the last page is just literally them on the bed.
Sorry, I can't spoiler the stuff I've said because if I did, the spoiler box doesn't appear to me when I have 'saved' it.