I slept with my doctoral supervisor and I wonder if this behavior is strange/toxic

[selenavivian]

I am going to write this from the third person, so that I can give names to the people involved. The person representing myself in this situation I will refer to as “Cassie”. I have many questions about this situation and want to know if this is some kind of toxic situation, if I am being used, and honestly, what is going on. I apologize for the length, but i wanted to be very clear and not leave out any details. Also I naively admit I am not sure any of this violates sexual consent, so I will just say there might be some things that seem like forceful sex, so if this is sensitive, trigger warning.

***Cassie, who is in a long-term, but open, relationship with Sam, met this man named Christopher. Christopher is well respected and established in Cassie’s field, and a professor of the same subject. Cassie and Christopher had an instant friendship and seemed to hit it off quite well, to a point where Sam suggested that Christopher liked Cassie. Cassie admitted she also liked Christopher. The did not live in the same city, but at the time Cassie and Christopher met, Cassie had already arranged to live in the same city as Christopher. Several months later Cassie is now a doctoral student of Christopher. As far as Cassie knows, Christopher is single. Sometime into Cassie’s studies, she went with Christopher to an academic conference for a few days. Christopher offered a ride to Cassie and another student, and they all went together, but stayed in different locations. At the end of the conference, Christopher’s car broke down on the way home. The other student left immediately but Cassie held out hope the car would be repaired in the morning, opting to stay instead of go home because she did not have a house key and didn’t want to wake her partner up at 5am. Cassie also, as a student, offered to stay in a room with Christopher to save money. This was a room with two separate beds, and Cassie had done this before with other friends and travelling partners, so thought nothing of the situation. Cassie and Christopher were both tired and decided to just hang out and watch some videos and talk instead of doing their respected work. As people that had been friends before, this was not at all strange to Cassie. Several hours later, Cassie gave Christopher a hug and went to go to sleep, but Christopher accidentally gave Cassie too long of a hug, in a “lost control” sort of way. Cassie immediately realized something was wrong at this time, and after a discussion and one thing leading to another, both of them admitting they liked each other, the two of them went to go to sleep together. Cassie was just going to go to sleep, figuring that it was too soon to approach this person for sex, but shortly after they lied down Christopher began to grope her and kiss her. At this point she realized he did want sex, and they did have sex. Cassie found out at this time that Christopher was married, but in a type of “don’t ask-don’t tell” open relationship. Christopher and Cassie then dated for a while, and went the opportunity arose, they had sex. Cassie, being in several long-term relationships, including all types of kink, and also having had several one-night stands, found Christopher’s sexual behavior strange. For example, even though she has participated in up-to weeks long of tease and denial, she had never had sex with someone that seemed so out of control and urgent once things began. Cassie originally thought this was due to inexperience but upon finding out Christopher was married for at least three years, decided this couldn’t be the case. For example, the groping, kissing, and dry-humping leading into sex always seemed like Christopher hadn’t had sex in maybe, months, and could not stop, and was completely out of control. Cassie questioned whether there would be the ability to stop if the opportunity arose. On top of that, Cassie continually questions whether the marriage is actually open, since Cassie knows many couples with open relationships and none have such secrecy surrounding it. Cassie also noted that this type of out-of-control behavior she has only experienced once in her life – when her mom’s sex-offender ex would give her hugs that lasted just a little bit too long as a teenager. Cassie and Christopher don’t have sex often, most of the relationship between them outside of doctoral supervision involves date-like activities instead. ***

my biggest questions are: does any of this raise any red flags? Is this strange behavior, or is it possible that the person in question is just inexperienced or perhaps even repressed sexually? I don’t know anything about his sex life or past relationships, only that his current one is at least three years long. The person in question is also one of those people that seems super nice and shy to an awkward point outside of sexual activities, so the difference in behavior – super-passive to almost borderline aggressive, is a big anomaly.
Any help/advice is greatly appreciated. Thank you.

[Hooo!]

So you have sex with your married professor and ask if it raises any red flags

The question itself raises some in me

[Minikimini]

Thank you, Hooo! for reading and condensing that wall of font.