I believe this is very common. Even as an alpha guy i think about it with my wife. For me i'd tickle both of them but the idea is very interesting if played out right.
Didn't work out time-wise with the initial person so I'm still open to looking for people who wanna chat/RP about cuckold tickling. Kinks are feet, tickling, orgasm denial/forced orgasms, and especially verbal teasing/humiliation (drives me crazy lol). Looking to chat primarily on this platform. Willing to share a pic of my girl's feet by request (she is aware of it). Check my profile for more info. Thanks!