There was a party at the Thousand Sunny, everyone was happy dancing and drinking.

And as always, sanji weren't good with alcohol. When he was on his way to his room, drunk, he tripped but you, who was coming out of the bathroom, managed to catch him. He stared at you, and without saying anything, he kissed you. You knew that was a bad thing, since he was drunk, you felt bad for not having taken him away from you instead of reciprocating him

So the next day you were avoiding him.