Dong Ha, a pure young man with a sunny appearance, moves into the city's shared house with excitement ahead of entering college. Dong Ha met suspicious members at the house where he will stay for a month. House leader Ju Won is particularly feisty with Dong Ha, and Dong Ha, who doesn't know their identity, begins a close cohabitation with members with vampire secrets!

Tenant Dong Ha tries to get close to the cold Ju Won, but he runs into an unexpected misunderstanding, and Eun Ho and Gyu Min, who want fresh human blood, are struggling to see Dong Ha, who is not able to absorb blood. However, the house members' minds fluctuate with the surprise proposal of Sun Jae, who said he liked Dong Ha.

Sun Jae, Gyu Min, and Eun Ho do their best to fatten up Dong Ha. Watching coldly from the side, Ju Won disrupts the mood, shocking the others. Meanwhile, Sun Jae begins to suspect Dong Ha’s blood might be especially delicious and admits he’s growing more interested in him…

Dong Ha’s neck is accidentally cut, awakening Ju Won’s vampire instincts. Struggling to suppress his urges, Ju Won’s body weakens, forcing him to call Sun Jae for help. Back at the house, Sun Jae grows suspicious of Ju Won’s feelings for Dong Ha as things take a passionate turn.

Juwon is haunted by nightmares and unable to sleep alone, so Dongha stays by his side. Meanwhile, Eunho and Gyumin attempt to sneak a taste of Dongha’s blood but are caught when Juwon blocks their way. The next day, Juwon visits the café where Dongha works and encounters a mysterious boy who sees through his vampire identity. To Juwon’s shock, the boy even urges him to pursue Dongha.

A misunderstanding sparks a quarrel between Juwon and Dongha, leaving Juwon discouraged. Sunjae suggests a trip to clear his mind, which unexpectedly turns into a group trip. Seeing the ocean for the first time, Dongha is overjoyed, stirring Juwon’s feelings as the two grow closer. Yet Sunjae warns Juwon once again that he cannot love a human, and between the three of them, love and jealousy quietly begin to surface.