1. Not being focused on the relationship at hand
On night one, Scott was escorted out by Hannah (demonstrated in the above gif) because he had a girlfriend back at home. Being involved in two relationships at once, and leading another person on when you don't have the intention of "going the distance" with them is never okay, and creates a great deal of confusion and manipulation. Don't pull a Scott on someone else, and never let someone else pull a Scott on you.
2. Being too clingy and possessive.
This red flag was demonstrated most notably by Luke P. on a group date, where he continually pulled Hannah away from the other guys on the date and essentially tried to make the entire affair a one-on-one. While in the real world, a person, hopefully, won't have multiple relationships to juggle, we all have multiple commitments that we need to devote time to: school, work, friendships, family, health, and personal issues. If your significant other is convinced that the only way to preserve your relationship is for them to be constantly by your side or in your face, there might be deeper issues that need addressing.
3. They stop getting along with other people in their life.
This is another trait exhibited by Luke P. And I don't mean having a falling out with one or two people. I mean entire groups of people - friends, family, coworkers, etc. - no longer wishing to associate with your significant other. After Luke P. began lying and being manipulative in regards to the other men in the house, they all began to dislike and even come to hate him and his behavior. A few even went so far as to call him a psychopath. Some people try to keep up appearances of perfection around someone they have feelings for and let the rest of the world see their true selves. If many outsiders to the relationship are finding issues with your S.O., maybe they're seeing something you're not.
4. Being physically aggressive.
Yet again, Luke P. is the culprit here. During a match of rugby on the show, he picked up a contestant on the opposing team - who was not exhibiting any aggressive behavior himself - and threw him to the ground and allegedly kneeing him in the head while he was down. Granted, rugby is an intense, physically demanding game, but being able to recognize what is part of the game and what isn't is very important here. If your S.O. is getting physically aggressive or threatening physical harm to others, they might one day direct that behavior towards you, no matter how nice or sweet they may seem.
5. Being overly controlling.
Surprise, surprise. Another red flag courtesy of Luke P. After Hannah tried to send Luke home after he wasn't emotional or real on their one-on-one date, he comes back, essentially telling her that he won't take no for an answer. It's one thing to fight for a relationship you believe is worth it and has potential, but it's another to not respect someone's right to make their own decisions. Hannah gave him ample time to be real and exhibit the traits she wanted to see from someone who would be her future husband, and he didn't deliver. He didn't respect her decision to send him home, and essentially acted as though he knows what's best for her, even when it obviously contradicts her own actions. If your S.O. tries to make all of your decisions for you and does not respect your own thoughts and opinions, maybe they shouldn't have the privilege of being in your life in the first place.
6. Sex-shaming.
At this point, I don't even need to say this is attributed to Luke P. In the previews for the rest of the season, it's been revealed that, after Hannah allowed him to come back and have one final chance to prove himself, Luke sex-shames her. He is quite religious and believes that sex in a marriage should be kept pure and he doesn't want her pursuing physical relationships with any of the other men, and blatantly states that if she has had sex, he would want to be sent home. While keeping with one's religious beliefs should be applauded, the way Luke goes about this is absolutely appalling. If a person has an issue with another person's past, then it's okay to not wish to pursue a relationship with them. However, it is never okay for someone to blatantly tell another person what they can and cannot do in the confines of their relationship. A person's past cannot be changed, and if your S.O. criticizes you for decisions you made previously, they have no right to ask you for anything. As Hannah so expertly puts it, "I don't owe you anything."
