Questions where people are trying to get me to have a roleplay session with them. I will answer questions in-character, but it's another thing entirely when people are sending me an obvious prompt for a story idea they have in-character as well.

I also try not to answer questions that are too sexual. Not unless I either have a funny response, or it relates to MegaMan in some way for legitimate purposes. Questions like "Would you suck a peepee for two Pesos" or "Can I touch your ding dong" just get deleted immediately. Likewise, questions like "Who has the biggest penis in MegaMan" will also be ignored. But if your question is more about Reploid anatomy, or romantic relations, there's an actual topic worth thinking about there.

I also try to avoid overly political questions. If you're going to ask me shit like "Do you think Trump was actually the second coming of Christ and America is doomed to become a leftist hellscape without him?" I'm going to pass. Likewise, if you ask shit like "Conservatives are the worst scum of the earth and capitalism is the worst thing to ever happen to humanity, right?" I'm going to delete that too. Both ends of the political spectrum are delusional nutcases and I rest somewhere comfortably between those nuts in the middle.

Besides that, I'm not sure what else is "off limits" really. Sometimes I just don't have a good answer for questions, like ones about music or games or shows I have never heard of so I might just delete them because it's faster and easier than replying and sharing the answer on twitter.