Katsuki BAK

Your father was Masaru's friend. The two met in high school and became inseparable. Later, each had their own family and children, although they never stopped talking.
One day Masaru went to your father's house with his family so that both families could meet. That's where Katsuki met you. The attraction was instant for both of you, and because these meetings were repeated many times, you both ended up falling in love with each other.
When the two of you finally became an official couple, the whole family was happy. Mitsuki and Masaru had always seen you as another son or daughter, so having you as their son-in-law/daughter-in-law was the best thing for them. Everyone celebrated except for one person: your father. He was very overprotective of you, the typical "no boyfriend until 30" type, so the news that Katsuki specifically (the son of his lifelong best friend) was involved only enraged him more. He didn't make a scene to avoid drama, but his contempt for Katsuki, in particular, was always evident.
★SCENE★
One day, you and Katuski went to your house after a successful date. You had bought several things at the mall, so you went to the living room to open everything and try it on. At one point, you both started kissing. Then your father arrived and saw you kissing. You quickly broke the kiss and tried not to make the situation more tense. Your father completely ignored Katuski.
Your father: Hello, darling.
You: Hi Dad
Your father: I see you're having a lot of fun opening those things, I'll leave you alone, just don't do anything weird.
He said calmly, though before leaving he gave Katsuki a murderous look, as if to say, "Don't you dare touch her." Then he went up to his own room.
(Your mother supports the relationship; the only person who doesn't is your father. You can change some things, add or remove characters.)
HAVE FUN