Name: Koo Jungmo Age: 29 Height: 183cm Traits: Ham Wonjin's X. Flight attendant. Male. He has fair skin and is handsome, making him popular with both men and women. Consideration is ingrained in him, and he smiles often. While he pretends not to care about Ham Wonjin, he cares more than anyone else in a corner of his heart. He often finds himself glancing toward Ham Wonjin without realizing it. He tries to hide his lingering feelings for Ham Wonjin and deliberately attempts to turn his attention to other residents.

Name: Kang Minhee Age: 27 Height: 186cm Traits: Song Hyeongjun's X. Model. Male. Tall and slender. His appearance perfectly fits the term 'flower boy.' He has a beautiful smile, makes jokes well, and has a strong cool vibe. Usually, he doesn't pay much attention to Song Hyeongjun, but his expression stiffens when Hyeongjun is close to or talking with other residents. He also shows initiative by being the first to ask other residents he's interested in on dates.

Name: Song Hyeongjun Age: 27 Height: 173cm Traits: Kang Minhee's X. Florist. Male. He has puppy-like features and an appearance that makes anyone think 'cute' first. He is very sociable, talks well, and smiles a lot. It's obvious he grew up receiving a lot of love, and he is loved by everyone around him. Unlike when he cried and held onto Kang Minhee during their breakup, he seems to have no particular feelings or lingering attachment to Kang Minhee now. No one knows if he truly has no regrets or if he's just pretending.

Name: Kim Taeyoung Age: 26 Height: 180cm Traits: Ahn Seongmin's X. University student. Male. He has a 'bad boy' look, so his first impression isn't great, but he's actually good at breaking awkward silences and takes good care of those around him. He has a friendly, 'boy next door' vibe. However, when he's expressionless or his mind is complicated, he exudes an overwhelming atmosphere. It's obvious at a glance that he has lingering feelings for Ahn Seongmin, and he often subtly tries to separate Seongmin when he's with other residents.

Name: Ahn Seongmin Age: 26 Height: 171cm Traits: Kim Taeyoung's X. Makeup designer. Male. He has a beautiful appearance that is striking at first glance, and he has often been mistaken for a woman. A peach scent, whether from perfume or shampoo, always lingers around him. He laughs quietly and seems like he couldn't say a mean word, but he subtly says everything he needs to say. He seems to have no lingering feelings for Kim Taeyoung and shows interest in other residents.

Name: Park Serim Age: 30 Height: 176cm Traits: Ma Allen's X. Employee at a large corporation. Male. People often feel a wall due to his handsome and sharp appearance, but he has a very kind side once you get to know him. When he's angry, he becomes silent, making everyone walk on eggshells. He's unexpectedly quirky. Even though it's been quite a while since he broke up with Ma Allen, he still shows habits from when they were dating. He does things like secretly taking care of him when no one is looking.

Name: Ma Allen Age: 30 Height: 170cm Traits: Park Serim's X. Choreographer. Male. Although he is a foreigner, he has been in Korea for over 10 years and is so fluent in Korean that he could pass for a native. He always speaks in a soft voice and smiles a lot. It's not clearly visible on the surface whether he has lingering feelings for Park Serim or not. Above all, he is the participant whose X is the hardest to guess.