[Spoiler Warning]
I just finished playing it and I actually enjoyed it. Shame that it just ended abruptly tho. Would have been great if there was an ending CG to top it off, but understandable that you rushed it for the jam.
There were some grammatical errors, which you guys did point out in the vn itself. but it was nothing too bad that it ruined the experience.
The story was nothing different, I actually sensed that there was gonna be a downfall after the lovely time they were having. Just a classic example of too good to be true. I also predicted she's gonna come back, I don't think it's hard to predict that. Despite that, it still was an enjoyable read for me. You were able to make Mai a cute character, and I think that's all that really matters.
One last thing, I think you could have had close ups of her for specific moments. I think that would have added a big impact.