Head for the shower

Deciding to take a shower, you head for the stairs. The swim was refreshing, but you could use some soap.

As you pass your father's study on the way to the upstairs bathroom, you hear grunting and squeaking from within. Looking through the cracked door, you see Greg sitting by his desk, a mysterious naked teenager bucking in his lap. Her massive breasts, along with her blonde ponytail, bounce up and down as your fully-clothed father thrusts into her.

As you watch the display, you feel your cock stiffening. Some part of you wants to join in, but another part really wants that shower...and a third part thinks a threesome with your own dad is just too weird. You hesitate in the doorway, staying out of sight.