CHRIS BROWNFriend Denies RapeSAYS ALLRED'S EXPLOITING THE WOMAN

Chris Brown's friend, who's been accused of raping a woman while partying at Brown's house, says there's zero evidence of a crime ... and he's blasting Gloria Allred for going after him. 

Lowell Grissom Jr. is the man Allred's anonymous client claims raped her twice during the party. The allegations are pretty graphic -- in her lawsuit, the woman says Grissom grabbed her out of a bathroom and raped her. Then later, found her in a laundry room and raped her again.

But Grissom's attorney Anthony Willoughby tells TMZ ... the matter was fully investigated, and his client's name was cleared. He says, "Lowell vehemently denies these false and defaming accusations originated last year, ending with no arrests, no proof, an inconclusive rape kit and after a police investigation -- no charges filed.

He adds, "This civil lawsuit is a blatant attempt at a money grab and to harm the reputation of my client while encouraging PR noise for Gloria Allred while she exploits this young woman for her own financial gains and public persona."

Grissom's attorney says they're confident they'll win the case.