Maybe you can synchronize with his wife??

His turn of phrase makes it sound as if he believes you have been acting unprofessionally at work as a result of your period and he wants to avoid your irrational behaviour. If so, tactless though his approach might be, it's certainly better than sacking you.

That is a clear form of sexual harassment you can have him suspended for asking a question like that.

It may be time for a new boss, OP...

at least he's being honest about it he doesn't want to deal with any drama

That's the Trump's way. Your boss is direct when it comes to business.

This is just such a weird request on several levels. Firstly, what "shit" is he trying to avoid? I can think of nothing about a period that would disrupt a work environment so much that he would even notice, unless OP has severe cramps, menorrhagia, or hormone irregularities leading to missed days of work. (I am assuming here that OP is capable of managing a normal-flow, moderately-crampy period without talking/whining about it a lot.) Secondly, how would he avoid whatever consequences he thinks come with a period? Would he just not talk to her for 5 to 7 days, fearing that his face would be ripped off in some kind of Hulk-esque rage attack? LOL His words seem to reveal a juvenile, "grossed-out" mindset about periods, and yet he thinks it's appropriate to ask invasive questions about it, too. It's juuuuust creepy enough to be harassment, in my opinion.

tell him your cycle is really messed up & you menstruate 3 weeks a month... you won't ever have to deal with him :)

That is kinda creepy he asked that because it's none of his business. Way too personal for work and he should've realized that.

and that's his business how? pretty sure he can't ask you about that..