It seems to have lots of potential~
It's a story you can definetely look forward to, would definitely recommend you try it out~! (Slight spoiler of version 0.1.0 here:<spoiler>Though making the girls aware of the mcs relationship might not have been a good idea...</spoiler>)
Overall the conversation of the girls are fun and interesting while maybe a bit too horny~ xD
The things that bother me a bit are the mcs overall design he seems too short being or almost the same size as Hana, he lacks muscles even when described as fit, in conversations he tends to step on landmines and anyone with some knowledge about relationships with women or conversing with others would most likely be able to easily dodge them, also I think he could need a genitalia upgrade it looks quite small on his overall physique even if it might not be, well and his face is looking like a average nerdy hipsters or lame teacher trying to look youngers than he is rather than like described good looking or stud like college student.
I would suggest to up his overall design a bit making his height 180+ cm would be a good start and correspondingly increase his genitalia size and musculature making it fit more to the context and storyline.
I hope, you don't take this negatively Soft Whisper.
I'm only stating this to support this stories maximal potential, and don't want to kill your joy and interest on creating this series... in the first place I wouldn't make such a long comment if I found the series wasn't good and had no potential.
So have a nice day would be happy if you took my comment positively and Happy Halloween~ :)