I've met some mean rabbit monsters before...they're not big enough to be mounts, though, so I've never tried to train one.

Hmm...

[looks at the mom bunny rolling around on Charon's back. she needed a vacation from her babies from the looks of it, so...he puts her back on the ground and addresses her very politely]

...Ma'am, do you want to get your kids for us? There's enough hay for all of them.

[either this rabbit is very smart or animals just Get Lethe because she hoppin' back to her den]