Makoto Okazaki is your run of the mill high-schooler, a perfect bullying target and a closet pervert. One night he decides to return a DVD to a friend of his and ventures out into the night. He notices a person on a nearby rooftop. The person lunges at him before he is able to make sense of this, and bites into his neck, drinking blood.
This series contains examples of:
- A Date with Rosie Palms: Makoto engages in this in the first chapter.
- The Ageless: Vampires dont seem to age in this series.
- Daywalking Vampire: Makoto and others can walk around during the day, though it makes them dizzy and weak.
- The Drifter: The vampires in Happiness are homeless drifters always on the go, never staying in one place for too long.
- A God I Am Not: Yuki tells an entire cult that hes not the God they think he is.
- In a Single Bound: Makoto and other vampires can pull off massive jumps from rooftop to rooftop.
- Loser Protagonist: Makoto is bullied into buying food for the popular kids on a regular basis.
- The Men in Black: A group of them appear in chapter 15 and attempt to kidnap Makoto.
- Mysterious Waif: Nora the vampire girl.
- Our Vampires Are Different: They are day walking but with the sun clearly bothering them, sensing when another Vampire is near and being able to let out echoes that only other vampires can hear.
- Religion of Evil: Sakurane creates a cult worshipping the one they call God: the vampire they are keeping locked up in the basement, Yuki.
- Time Skip: The story skips 10 years after Makoto runs away from home, Yuki gets taken in by Sakurane, and the deaths of Shiraishi and her family.
- Another one occurs when Makoto was captured. Apparently he's been imprisoned for 10 years and being experimented on.
- Undead Barefooter: Nearly all the vampires go barefoot.
- What Have I Become?: Makoto struggles to resist his vampire urges.