Hayate the Combat Butler (2007) : 2x4

One day before valentines, Nagi is trying to make some chocolate for Hayate and decides to skip school. At school Nishizawa tries to give Hayate some "love chocolate" but insteads gives him obligation chocolate. Hinagiku realizes Nishizawa panicked and tells Hayate to exchange it. However after receiving the "love chocolate" Hayate is a bit confused on the love concept and asks Maria for help. Maria remembers that she had little/no experience with love either and becomes depressed/mad. However she decides to make some chocolate for Hayate. Nagi, after failing herself to make chocolate, tells Hayate to make some chocolate for her. Hayate meets Maria in the kitchen and they have a contest to make the best chocolate. Maria makes her chocolate super incredible, but when asked about who its for, she becomes embarrassed and runs outside. Hayate catches up to her and gives her some chocolate that he made, and says valentines is the time where people work harder just to see the person they treasure smile.