Arc the Lad (1999)

The story begins when high school student Kazuki Muto is killed one night saving a mysterious girl from a monster, only to wake up in his school dorm, believing it to have been a dream; however, he soon finds out that dream wasn't a dream at all when a giant serpentine monster attacks him and his sister. Tokiko Tsumura, the girl he saved, explains that the monster is a homunculus. Kazuki had been attacked and killed by it when he was rescuing her; however, she, feeling responsible for him, revived him by placing a Kakugane medallion in his chest, serving as a replacement heart.

High schooler Yūta Iridatsu has experienced “astral projection” i.e. his spirit has been separated from his body. He woke up in a mansion named Koraikan and met a cat spirit named Chiranosuke, who told him “You must find the Sacred Tome of Koraikan in order to return to your physical body.” While searching through corridors of Koraikan, Yūta bumped into underpants of its female residents, and doing so would, eh, create some big trouble for planet Earth.

Kouta has girl troubles of the supernatural sort. For some reason, he keeps attracting the attention (and affections) of animal spirits! Having spent most of his life in the country, Kouta is understandably nervous when he moves in with his grandma to attend a high school in the big city. He hoped to make a good impression, but having Chizuru, a beautiful fox spirit, hanging off his arm didn't seem to be the sort of image he wanted to have. She's not alone in her love for Kouta, either. Nozomu, a wolf spirit, as well as other youkai have their sights set on the hapless country boy.

As a prophecy of doom unfolds on the peaceful land of Britannia, a purehearted boy sets out on a journey of discovery — and revenge.

Toriko is a Japanese manga series written and illustrated by Mitsutoshi Shimabukuro. It has been serialized in Weekly Shōnen Jump since May 19, 2008, and has been collected into 25 tankōbon volumes by Shueisha as of July 4, 2013. It follows the adventure of Toriko, a Gourmet Hunter, as he searches for rare, diverse foods to complete a full-course meal. On his journey, he is accompanied by a timid chef who wants to improve his skills.

Sato is a high school boy in love with his best friend Hime, an unearthly beauty from another realm. So when she moves back to her home world to get married, Sato doesn’t think twice—he follows her and crashes the wedding. Then, after a kiss from Hime, he suddenly becomes the new groom! But here, Hime is a Ring Princess and her husband is destined to be the Ring King: a hero of immense power.

Genki is a boy who loves playing the Monster Rancher games and one day he's somehow transported into the world of the video game where he meets the girl Holly and the monsters Mochi, Suezo, Golem, Tiger and Hare. Together, they are searching for a way to revive the Phoenix, which is the only monster capable of stopping the evil Moo.

The skilled hunter Kikuru Madan has decided to retire out of fear of wasting his youth. One day, a guild staff member suggests that he go on a quest with a new female martial artist named Hitamu Kyan. However, she keeps getting hit by monsters one after another.

In a world where both men and monsters exist. Those who hunt the monsters are called Hunters. But in a small corner of the Hunter's world, there are those called Riders who bond with and coexist with monsters. With their Kizuna Ishi (Bonding Stones) that allow them to awaken the hidden power inside monsters, Riders live in secrecy together with their Otomon, the monsters they formed a connection with. Ryuto, a young boy living in the Rider village of Hakum, dreams of becoming the world's best Rider. Having just turned 12, he sets out to find his own Otomon for himself before the ceremony where he is given his own Kizuna Ishi. Together with his kind-hearted childhood friend Cheval, his inquisitive childhood friend Lilia, and his partner Naville, he sets out deep into the forest, and has a miraculous encounter with a Rathalos.

Armed with dual machine guns, an undead school girl, Makina Hoshimura, must hunt down 108 other undeads with the help of specially trained Buddhist monks in order to gain entry into Heaven. Based on manga written by Yoshiichi Akahito.