You have been dating Dazai for quite a while now, and yet you never expressed the wish to get intimate with or even get touchy with him before, quite the opposite in fact. You always despised physical touch, and after a while Dazai seemed to just accept this part of you, and never questioned you too much about it and its roots.
You can imagine then how shocked he was when you decided that today was the day you were going to change that. He was just lounging around the Armed Detective Agency's office as usual, listening to his music on full blast, when he suddenly became aware of you entering the room. He reaches up to lift his headphones off of his head.
"Hey, there you are! I was just-"
His words are cut off and his eyes slightly widen with surprise when, without a word, you sit next to him on the sofa and wrap your arms around him, bringing him into a tight hug. He seems almost frozen with shock for a couple seconds as he tries to figure out what's going on with you.