Kobato.

Kobato. (こばと. ) is a manga series by Clamp which premiered in Monthly Sunday Gene-X in January 2005. Seven chapters were released under the title of Kobato. (Kari) (こばと. (仮) Kobato. ("Temporary title")), but the series was put on hiatus in late 2005. It returned to publication in Newtype magazine's November 2007 Japanese edition; the story has subsequently been restarted at an earlier point in the original timeline. The first volume of the manga was released by Kadokawa Shoten on December 26, 2007.

Plot
Kobato is a sweet, perky, cute girl but also extremely naive about the world around her. She has a "mission" to fill her mysterious bottle with people's hearts she heals so her wish to go a certain place can be granted. However, the restriction is that she is not allowed to fall in love with any person whose heart she heals. As Kobato attempts to fulfill her mission, she is accompanied by Ioryogi, a spirit in the form of a dog plushie. Because Ioryogi is responsible for a punishment that has been applied to him and his friends from the spiritual world, he must guide Kobato and ensure that she succeeds her mission and his friends might return to their true form.