That will teach him a lesson about the vent stack!
You are correct.
Poor little guy. 
I opened the lid on one of my toilets once, and found a live frog. Not a tiny one, mind you.
I successfully relocated it* to the back yard.
*the frog. The toilet was relocated to a trash pile as part of an unrelated house remodel.
Regular rats show up in the toilet. Why not tree rats? Can rats swim up through the (urk) toilet? - The Straight Dope
If I were you, I’d contact a medical professional to inquire if you should get a rabies vaccine, even if you don’t think it bit you. Rabies is 99+% fatal once symptoms appear.
IANAD.
Rabid Toilet Squirrels? Band name!
Yeah, are your balls foaming at the mouth and acting all aggressive?
I’m not a doctor either, but according to the CDC:
I have a rare day off and I’m sitting here sipping coffee, listening to the squirrels race about the roof. It may behoove me to make a trip to Home Depot to get some wire netting of some sort and put some screens on the vent pipes to prevent a repeat performance.
When I left work yesterday, I told a coworker, “Well, I’m going home to check my squirrel traps.”
You know how we sometimes say that this or that person has “won the thread”?
It is my belief that Tully Mars has won the emoticon :eek:.
yo
I usually do not advocate this sort of thing, but if they are biting you on the testicles,this is what you need.
Well, I shouldn’t have that problem again. All of the vent pipes are now capped with stainless steel hardware cloth. I did not realize the master bath vent pipe was 4" I.D. Given that, I’m surprised that I have not been surprised before now.
Good to know, thanks.
Thank you for the new euphemism. 
I was out walking once, minding my own business, when a squirrel crossed my path walking backwards and dragging an intact Danish that was as big as he was. You could almost hear the thought going through his mind: “Oh, boy! Oh, boy! Oh, boy! What a catch!”
It was wrapped in a napkin, so I thought I’d help the little guy out by unwrapping it for him. Big mistake.
When I bent over, he backed away nervously and sat there watching me, waiting to see what would happen next. As soon as I touched it, he was all over my hand and forearm, growling and gnashing his teeth.
He didn’t bite me, but he backed off when I shouted “Hey!” and sat there huffing and glaring at me with an expression on his face I never knew squirrels could have.
I felt kind of silly, since I knew it was his breakfast (and lunch, and dinner), and I really had no business interfering with his efforts. It was also kind of dumb for me to think a wild animal would know I was trying to help, rather than stealing his booty.
So I just backed away slowly and let him get on with it. He grabbed ahold of the roll and resumed tugging it backwards toward his nest. I’ve always hoped another predator didn’t get him before he got home, and that he enjoyed his meal(s).
I can visualize a hawk sitting in a tree, “Look! Dinner and dessert!”
I saw a red-tail hawk nab a large squirrel once. I was impressed the he could fly off with it.
Q: Aren’t you glad that you didn’t piss off the squirrel?
I hope he did, too.
A: Better to piss of the squirrel than to piss on the squirrel.