At the Sanzenin Mansion, Hayate finds a note written by Nagi that was pinned to the kitchen door telling him not to enter. This is not present in the manga
Additionally, in this episode this event took place on February 13th, whereas in the manga, it took place on the 14th.
After having sent Hayate off to school, Maria watches Nagi attempt to make Valentines day chocolate for Hayate. This is not present in the manga.
At Rental Video V Tachibana, as Ayumu has Wataru try her chocolate, he is seen reading a magazine entitled "News Month". In the manga, it was called "News Week".
Later at night in the Sanzenin Mansion, Nagi attempts to make her chocolate "heart shaped" resulting in a large explosion. This is not present in the manga.
In the student council room, as Hinagiku was eating the Valentines day chocolate she had received earlier, she contemplates on buying some milk at the cafeteria but worries that she'd receive more chocolate from other students before deciding to go to a convenience store instead. This is not present in this episode.
Back at the Sanzenin Mansion, Maria teaches Nagi how to properly make homemade chocolate. This is not present in the manga.
At the front gate of Hakuo Academy, before entering the academy, Ayumu thinks to herself on how big the school campus is. This is absent in this episode.
After having noticed that Hayate had received "obligation chocolate" from Ayumu, Hinagiku tells him to go to Ayumu to exchange them. In this episode, the wrapping for the "obligation chocolate" is shown to be black. In the manga, it was pinstriped.
Additionally, in this episode the time on the Hakuo clock tower read 3:30. In the manga, it was 4:45.
At the Sanzenin Mansion, after having asked Linn on what love is, Hayate questions him as to why he was at the Sanzenin Mansion. This is not present in the manga.
Afterwards, after Maria greeted him, Hayate tries to introduce her to Linn before realizing that she couldn't see him. This is also not present in the manga.
Inside the kitchen, Nagi questions the appearance of her homemade chocolate and tastes it realizing that it was inedible. This is not present in the manga.
As Hayate questions Maria if she had any experience in romance, she is shown to be holding a broom. In the manga, she wasn't.
Afterwards, having felt embarrassed, angry and unable to help him with his problem, Maria asks Hayate not to tell Nagi about their conversation. This is not present in this episode.
As Nagi ordered Hayate to make her Valentines day chocolate, her outfit had been altered for this scene. In this episode, Nagi wore a black turtle neck and white over the knee socks. In the manga, Nagi wore a open button up short sleeved shirt over her turtle neck and had black over the knee socks.
Additionally, this scene takes place at night. In the manga, it took place during the day.
After having finished making her Valentines day chocolate, Maria checks on Hayate's. Much to her surprise, she finds that he had made a chocolate swan. In this episode the swan was shown to be made out of white chocolate and was on a white plate with a blue stripe. In the manga, the swan was made out of milk/dark chocolate and was on a plain white plate.
At Rental Video V Tachibana, Saki drops a piece of chocolate cake on the floor. After seeing that it has caught his attention, Saki immediately apologizes to Wataru, who then tastes the icing from the cake and gives her a smile and a reassuring thumbs up. This is not present in the manga.
Afterwards, the scenes depicting Ayumu looking outside while on her family's apartment balcony and Hinagiku looking at the "obligation chocolate" she had received earlier are not present in the manga.
Inside the Sanzenin Mansion, Nagi is shown sleeping on a sofa while having a dream of Hayate tasting her homemade chocolate. This is not present in the manga.
After Hayate had made Maria upset by asking if she had any romantic experience, Linn can be seen sitting on a tree branch reading a Shounen Sunday magazine.