Love the artstyle of the game. I'll definitely put the game on my watch list.
Regarding the NTR content:
Normally i'd avoid these types of games like the plague. It's just not for me.
Nonetheless if this type of content is at least somewhat avoidable i don't see too much of a problem with it.
I also like the idea, that you can avoid it in a more organic way, instead of simply with a hard disable option at the beginning of the game. Makes it feel like you somewhat earned it. Which would be even more the case if for every potential NTR scene there was a reverse scene if you beat certain criteria that make the MC the focus.
On the concept of Brad:
A potential rival - in my opinion - should never be perfect or idolized in these types of games or it will just drift into pure NTR territory. The MC has to be able to, through some effort and making the right choices, surpass his rival and not just come close or match him. And he should have a feature that the rival doesn't posses and can't ever posses. Something that makes him at least somewhat unique. Most games go the easy route and simply remove any potential rivals to the MC outright, but i guess that's not what you've planned for the story.
Hope this didn't come of as too ranty. Like I said, love the game. Hope you'll keep on making it.