RIBBLE Valley Nigel Evans pushed a young man into a darkened room at Westminster and sexually assaulted him, a jury has heard.
The alleged victim told Preston Crown Court that ‘very quickly’ the MP ‘put his arms all over me and tried to kiss me’.
The man pulled away and then left the room ‘as quickly as possible’, he said.
He is one of seven young men that Evans, 56, is said to have assaulted.
The Westminster worker said he did not report the alleged incident at the time because he gave ‘the benefit of the doubt’ to the defendant who he considered ‘one of the nice guys’.
He added that people in Parliament ‘don't tend to have confidence in reporting anything about MPs’.
But he said he came forward to the police following the widespread reporting of Evans's initial arrest last year.
The incident is said to have taken place in a kitchen along the Deputy Speaker's Corridor in February 2011.
The complainant was drinking in a group with Evans in the Strangers' Bar at the House of Commons when the MP invited him, a friend and others to join him for champagne in his offices.
During the evening the alleged victim said he was invited by Evans to look at a nearby newly-fitted kitchen, the court heard.
He said the Ribble Valley MP opened the door and then with his left hand pushed him into the room.
The complainant said: "It was pitch black and then very quickly he kind of came forward and put his arms all over me and tried to kiss me.
"Then he took my hand and placed it on his erect penis. I felt his lips on mine at that point.
"He touched my crotch, he touched my bum...over the top of my clothing.
"I remember him saying something like 'you're gorgeous'. I didn't say anything because I was in shock."
He said he ‘gathered his senses’ and pushed him off.
He told a number of people about the alleged incident in the days that followed but did not make an official complaint.
He told the court: "Because of how much I liked Nigel I think I decided to convince myself it was a one-off and that he got carried away, and he overstepped the line. So I gave him the benefit of the doubt.
"And in Parliament, people don't tend to have confidence in reporting anything about MPs."
The court heard that Evans sent the complainant a Facebook message several days after the kitchen incident.
The MP wrote: "Hi (the alleged victim), my mobile number is ...., great to see you the other day."
The young man responded: "Hi. Thanks for allowing us to gatecrash your drinks. We (he and his friend) both had fun."
Evans then replied: "Yep, great fun!"
Evans denies one rape, two indecent assaults and six sexual assaults said to have taken place on various dates between 2002 and last year.