Girlfriend cheated as a college freshman

She cheated with a guy named Matt who was given a blowjob the details of the it are below and is a near replica of what she told me and her best friend about it.

She told me she was working on a chemistry problem set with Matt and another female friend . Eventually her friend left and it was just herself and Matt. She said Matt and her ending up making out on the couch in his dorm and quickly Matt had pulled her shirt down (she didn’t have a bra on ). She was still wearing a skirt and after a few mins of kissing/getting felt up she said she told Matt she had a boyfriend and was feeling guilty and shouldnt have even gone this far. She said she was going to leave but right then Matt pulled up her skirt and pushed her legs apart. He then said “well he’s not here right now and he won’t know”, as he quickly pulled her green thong to the side and started eating her out and he stuck a finger in her while holding her thong to the side. She said she felt guilty but was enjoying having her pussy eaten and fingered. Matt parted her labia and began to kiss and lick her clit .She started moaning which encouraged matt to continue and a second finger joined the first in her pussy. This went on for about maybe 5 or so minutes until she came for him. she stated she felt very guilty for laying there while her thong was held to the side and that she had just come for him, and now realized She was going to have to reciprocate for him since Matt quickly took off his boxers and once his penis was out he told her she had to “use your mouth on it” and then said “I think thats fair I used my mouth down there on you.” His dick was a bit thicker than mine (but shorter) with a thick head and Matt was circumcised (I am uncircumcised and prior to me she has only ever had circumcised cocks) . He stood up as She dropped down to her knees in front of his dorm couch and began sucking on his cock . Matt felt her tits up alot during the blowjob as she was still topless. Her head bobbed up and down as she sucked and licked his cock.
Eventually Matt came in her mouth (she said he didn’t warn her first he just started cumming while she was in the middle of blowing him) and she just kept her mouth over his penis while he finished. She swallowed it likely because she was shocked he just came and because he encouraged/told her to swallow it.
She intially expected he was going to cum on her tits and she would have preferred that .
Although she said she felt guilty for cheating I think she enjoyed Matt and she was the one to specifically comment that matt was circumcised and that it was different for her.

Source: reddit.com/r/sexystories/comments/pmzicl/girlfriend_cheated_as_a_college_freshman