Mysir from Café Enchanté is one I really enjoyed because I liked the story's progression and the bittersweet ending! A special mention goes to Alice from Taisho x Alice as well; I started out quite annoyed and angry at him for being such a brute and insulting Arisu every five seconds, but in the end I quite liked him as I progressed through the game (I love when that happens, where I start out hating a character only for the game to make me change my mind at the end, haha.)
Now, one I don't particularly like is Yanagi from Collar x Malice. It's not like I hate his route or anything, I just think that as the final route, it didn't have as much emotion as the others. Given that he's the final route, I was quite excited thinking his route would be pure adrenaline, but aside from some revelations like the protagonist's past and the villain's reveal, I didn't find it as exciting as I thought it would be. But Yanagi is a really cool character and I like him despite that!