harem yes, but most of the girls are just like lil sisters to him. only a couple does he actually feel attracted to and as of yet there hasn't been much in the way of romance or intimacy...
At least there was no drama between the step sis and her. Mostly(in mangas) some people would be like a bixch and get jealous that the real child of the mom appeared. So im actually very happy that she just accepted her like a sister
But half the time im confused xD
They do explain how moves are done though, worth rereading