Just reached the first ending in this game- super cute! Makes me anxious to see what the rest of the game will be like if you go along with Zack.
I'd like to suggest that you include the "blackmail" tag. The MC is clearly being emotionally blackmailed by Zack to do things she wouldn't normally do.
The tag system I think is really good because it can help people avoid something they might find offensive or disturbing, or otherwise- find something that they like. I like blackmail in corruption games luckily, and am looking forward to the rest of the story.