Credit: James Devaney/

Does Scott Disick want to trade in one Kardashian sister for another?

As if!

Kim Kardashian LOL'd after one tabloid mag claimed that Disick -- her sister's Kourtney's man and father to little Mason -- was "in love" and "obsessed" with her.

"OMG Scott," Kim, 30, tweeted jokingly. "I had no idea u felt this way. Kourtney, we need to talk!"

Retorted Disick: "I had to confess, I couldn't take it anymore!"

Kourtney, 31, meanwhile, stayed above the fray entirely, tweeting a spiritual message courtesy of rapper/minister Rev Run: "'Stay prayed up.. You should ALWAYS be able to have a good sleep, knowing that Gods is ALWAYS awake" Love this! Prayer time!"