As the Manga goes on, I kinda pity our MC, It looks really hard to manage 3 HORNY GIRLS, not to mention keeping secrets about the curses of the other females...That aside, here how i rank them:
FIRST OF ALL THIS IS ONLY MY OPINION.
Fetish Ranking(Ranking based on my fetish):
#1 - Sensei
#2 - Rikka
#3 - Usui
Explanation:
Aight, Most of my fetishes includes someone like Sensei, Older but not too old, Probably older than me by 10years lower, another thing is that she's too erotic and sexy af but if we can say about love, i think she's obsessive which takes away some of the good parts, as for Rikka, of course she's the first but we are talking about fetish here so i kinda like how erotic the way she does it and i also like that wife side of hers, as for usui who comes in the last, I can't really say much, o do't know if she's good or bad or you know, but that's only my opinion.
Story Ranking(Ranking based on how i see the manga):
#1 - Rikka
#2 - Usui
#3 - Sensei
Explanation:
Aight, Rikka will be the first for she was the Original Love of our MC, since they are childhood friends, they've known each other for longest among the rest and rikka might really love him even without the curse of Zepar, as for Usui, She was aware of the situation yet as the manga goes on it seems like she was being consumed by lust(Well it's the curse) and seems to be forgetting about the rikka and mc dating thing...this will go same to sensei but with some worst part, as for sensei it seems like she was also consumed by lust(Well i mean, it was the curse first of all and it was the only way to calm them down)but a little bit obsessive like in the part where sensei said "In the end, i'll be Number 1", We don't know or we don't have much proof on who was the Most Loved by our MC...
AGAIN THIS IS ONLY MY OPINION.