Tart is portrayed as childish, mischievous, and hot-tempered, often serving as the most immature member of the alien trio. He dislikes being called “chibi” or “chibiko” (Japanese terms for runt or shorty), and he frequently responds to teasing with arguments, name calling, and tantrums. Compared to his comrades, Tart is far more prone to showing his emotions he laughs loudly when amused, pouts when frustrated, and occasionally bursts into tears when things do not go his way.

Despite his rudeness and enjoyment of making others cry, Tart’s personality is energetic and playfully curious, drawing frequent comparisons to Bu-Ling Huang (Pudding Fong), with whom he shares a childlike enthusiasm. His antics and immaturity often contrast sharply with Pai’s seriousness and Quiche’s sadistic amusement, making him the most openly expressive of the alien antagonists.

Tart is depicted as a small, childlike alien, reflecting his young age of around ten years old. He has medium-length brown hair, typically styled into two pigtails, and bronze-colored eyes. Like other members of his species, he possesses large, pointed ears. His light skin and youthful build emphasize his immaturity compared to his fellow aliens.

Tart’s outfit is relatively minimal and exposes much of his body, highlighting his agility and childlike nature. He wears a red shirt, black shorts, and bandages wrapped around his legs, and he notably does not wear shoes.

In the manga and related video games, Tart’s hair is instead colored red, designed to better complement his red-themed outfit and to match the appearance of his fellow aliens, Quiche and Pai.

Tart wields a weapon resembling a click-clack toy, which he uses both playfully and lethally in combat. His signature attacks include “Ho-Rai-Den” (封雷転, Closing Thunder Revolving) and “Hissatsu Hourai-Kyuu” (Certain Kill Treasure Ball), both of which draw on his alien powers.

Like his fellow aliens, Tart is capable of flight, teleportation, underwater respiration, and spirit extraction, the latter of which he demonstrates once in the series. His abilities are most strongly tied to plants, and he frequently manipulates vegetation in battle, often creating Chimera Animas fused with plant elements to fight on his behalf.

Bu-Ling Huang (Pudding Fong)
Tart’s most significant relationship is with Bu-Ling Huang, with whom he develops a mutual fondness despite being on opposing sides. In the manga, their relationship begins when Tart kidnaps Bu-Ling, though she remains cheerful and unbothered by his status as a villain. After Tart saves her from one of his own dangerous Chimera Animas, Bu-Ling begins to see him as a friend and affectionately nicknames him “Tar-Tar” (Taru-Taru). By the conclusion of the manga, Bu-Ling kisses him and slips a candy drop into his mouth as a parting gift. Tart responds that he might one day return to Earth—both for the candy and to see Bu-Ling again.

In the anime adaptation, their bond is explored in a slightly different way. While underground together, Bu-Ling remains cheerful despite their dire situation, and Tart initially tries to ignore her. However, when Bu-Ling begins to suffocate from lack of air, Tart teleports them both to safety, effectively saving her life. Later, near the end of the series, he catches Bu-Ling when she collapses from exhaustion, admitting that he no longer enjoys fighting. Bu-Ling encourages him by saying that with him by her side she feels “100 times stronger,” reinforcing their emotional connection.

Ichigo Momomiya
Like his comrades, Tart frequently opposes Ichigo, often mocking or insulting her during battles. While his hostility toward her is not rooted in obsession (unlike Quiche’s fixation), his antagonism reflects his struggle to maintain loyalty to his people while being influenced by his growing bond with Bu-Ling.

Quiche and Pai
Tart works alongside Quiche and Pai, though his childish temperament sometimes puts him at odds with their more mature personalities. He looks up to both as comrades but frequently clashes with Quiche’s playfulness and Pai’s seriousness. Despite their differences, they share a strong loyalty to their mission and to their endangered race.