Ray J Threatens to Sue Kim Kardashian Over Hulu Show for Insinuating Assault

Ray J seems serious about suing Kim Kardashian for her comment on her Hulu show that Ray J may have stuck something up her butt while she was sleeping.

Ray remains furious about the first episode of the show ... when Kim fretted there might be a second sex tape. She told her fam she was 99.9% sure there wasn't one, but then suggested if there was anything sexual in another tape ... Ray may have stuck a dildo up her butt while she was sound asleep.

Kim follows it up on the show by saying "It's completely illegal" and then asks her lawyer to "scare the s*** out of this guy."

Ray says it's all an outrageous lie to suggest he sexually assaulted Kim, and he says he's seriously considering a defamation lawsuit.

As we reported, Ray also says there IS a second sex tape -- the Cabo sex tape and another that was shot in Santa Barbara -- and he says Kris even watched the tapes and chose the one to distribute in which Kim looked the best. Kris has denied she had a hand in the release of the tape.

Kris took a lie detector test on 'The Late Late Show' a few days ago and, according to the polygrapher, was honest when she said she didn't orchestrate the deal.

Speaking of the sex tape, Kim has denied she had anything to do with the release, but Ray says she's absolutely lying, and showed the contract he signed with Vivid Entertainment where the sex tapes are chronicled in writing and he says Kim's the one who wrote it ... and her fingerprints -- literally her fingerprints -- are on the paper.