As a kid I used to think that Liquid Plumber was a superhero, like Aquaman for sewer pipes.

(no.  i never thought that.  but now i do.  just go along with it.)

My first thought would be the Liquidator from Darkwing Duck.
Liquidator
I mean, obviously it makes sense to have someone liquid that can get through all those pipes.  But a villainous dog that talks like an infomercial may not be my best bet.

And then I remembered (even though i totally didn’t and am just making this all up for this blog post right now) the perfect hero of my toilet dreams/nightmares…  Sewer Urchin!
Sewer Urchin
Beloved character from what is probably the greatest cartoon of all time, The Tick!  He actually gets more powerful when he’s in the sewers.  They’re his “surf” (compared to his “turf,” as it were).  And he’s a good guy!  Even better, give him Fish Boy (lost prince of Atlantis) as a sidekick!  It’d be awesome!  Or at least as awesome as a superhero duo fighting in other people’s excrement can be.

Which brings me to this:  Never shake hands with a Doat.  You have no idea where they’ve been.  And you really don’t want to.

Plus… they don’t actually have hands.

(and if you think this was just an excuse for me to post links to cartoons, congratulations!  you’ve been paying attention!)