The diary starts off with Chibi-Usa's first day at school. This is when she first meets her friend, Momoko-chan. Chibi-Usa tells the Momoko her name. Momoko says it's cute just like the new girl's name Lyrica-chan. Lyrica then doubles over and gets a boy to escort her home.

The next day at school, the boy who walked Lyrica home is missing. Lyrica says she knows nothing. Later Chibi-Usa, Momoko, and Lyrica are walking together. Lyrica remarks that Chibi-Usa has rosy cheeks that look delicious. Then she gets dizzy and has another boy walk her home.

When the teacher sees Lyrica is missing she tells Chibi-Usa to look for her. She sees Lyrica in the garden eating a flower.Chibi-Usa tells the senshi about Lyrica and they tell her Lyrica must be a vampire. Makoto tells her to eat a lot of garlic and then see if Lyrica reacts to it.

The next day at school Lyrica is not there. The teacher asks Chibi-Usa and three of her friends to take Lyrica's work to her house. They do and are confronted by Lyrica's mother, who reacts to Chibi-Usa's breath.

Lyrica's mother invites them in and says Lyrica couldn't be a vampire. They leave but then notice that Momoko is missing. They go back in and see that Momoko has two bite marks on her neck. Lyrica's mother laughs and then Lyrica appears. They say that they will take everyone's blood.Then Sailor Venus and Sailormoon appear. The destroy the two vampires. Later Chibi-Usa dreams of becoming a soldier too.