There was a whole episode dedicated to a robot hedgehog seducing Sonic.

This is Robotnik's Girlfriend Katella who tries to force him into marriage before Amy Rose came on the scene.

This show had a weird obsession with Robotnik's butt...

This show just did a lot of weird things with Robotnik...

Sonic got in on the action too...

...and tails,,,

...yeah...

And last but not least, Sonic's Feet. You're welcome or I'm sorry, whichever is more appropriate.