Tell him straight up that it's not okay. Family relationships should be based on respect and appropriate behavior. Don't be afraid to be firm. For example, say 'I'm not interested in this kind of relationship with you. We are cousins and this is wrong.'
First, don't blame yourself. This is his inappropriate behavior. You should make it clear that you value your family relationship in a proper way. If you are worried about hurting his feelings, you can still be gentle but firm. For example, 'I care about you as my cousin, but this seductive behavior is unacceptable. Let's keep our relationship normal and healthy.'
React calmly. Just say 'no' clearly. There's no need to be mean or judgmental, but be straightforward about your lack of interest.
Hermione would probably be very confused at first. Snape has always been a rather intimidating and strict teacher, so his sudden change in behavior would be quite a shock. She might initially think it's some sort of trick or test.
If this happens in a story, first, you can talk to your wife openly about how you feel. Make sure she is on the same page as you in terms of loyalty. Then, you might consider having a serious conversation with your roommate. Let him know that his behavior is inappropriate and unacceptable.
I would immediately interrupt and say that this is a private and inappropriate matter that should not be shared. It's important to set boundaries and uphold good taste in conversation.
The gay person should firmly reject the advances and distance themselves from the married man. They can also consider reporting the behavior if it makes them feel harassed.
In a story where a husband's brother seduces his wife, it's a complex situation. Firstly, the wife may be in a state of shock and confusion. She may initially try to fend off the advances discreetly to avoid a big family feud. However, if it continues, she may have to tell her husband. This will then lead to a maelstrom of emotions. The husband may be angry at his brother and also at his wife for not telling him sooner. The family structure may start to crumble as a result, with everyone's relationships in turmoil.
One immediate step is to be clear with your cousin. Say 'no' firmly and let them know their behavior is unacceptable. For example, if they make inappropriate comments, respond with a serious 'Stop that, it's not appropriate'.
This is a very difficult situation. First, it's important to firmly and clearly tell your cousin that this behavior is unacceptable. You have the right to set boundaries. Then, you might consider avoiding being alone with your cousin for a while. If the situation continues or makes you uncomfortable, it could be a good idea to talk to a trusted adult outside of the family, like a counselor or a family friend who can give objective advice.
I think the most memorable part was when my cousin introduced me to his group of gay friends. They were all so warm and friendly. We had a big party at his place. There was great music, delicious food, and lots of laughter. It made me realize how much my cousin had found a community that accepted and loved him for who he was, and I was glad to be a part of that moment in some small way.
Well, my gay cousin and I once went to a pride parade together. It was such an amazing experience. We saw so many people being their true selves, and it made my cousin feel really accepted. He was beaming the whole time, and we got some really cool rainbow stuff. It was a day full of love and celebration.