Thanks! ED3 happens when the player character demonstrates more trust in Brandon, but comes off as mean or unfriendly otherwise. So you should follow the tips to achieve ED3/4 (the hints we've shared in the comments below, but I'll copy & paste them here) but aside from these, you shouldn't be too friendly to Brandon.
- On September 23, say that you're sorry to hear about classmates making fun of him.
- On September 29, say that while it's not the same situation, you changed schools recently.
- On October 6, say that you know what he means, instead of just saying "that's rough".
- On October 11, say that you should finally make an account.
- On October 15, say that your friends don't know the real you.
- On October 25, say that it makes sense to have doubt.
- On November 14, say that there's a reason for it, and it's that you got too nervous.