You accept that you're not riding Steve; Steve is carrying you. You release the reins. It's in Steve's... hands? now.
You approach Lily's trap at a run. Steve leaps into the air like a four-legged, half-ton ballet dancer.
Halfway through his arch, you realize why you shouldn't have dropped the reins.
You fall into the hole of unspeakable things. Bank boys tumble on top of you.
Using the umbrella, you battle your way out.
You search for Lily and Steve, but don't see them -- only angry Banks.