Manga by author Takahashi Rumiko - Status ongoing

What would you do if a tiger skin bikini-clad alien followed you to school every day? Poor Ataru's life has never returned to normal since volatile extraterrestrial princess Lum fell for him. Now an excruciatingly wealthy and genteel rival, Mendo, adds to Ataru's torment. Not to mention an unending stream of extraordinary classroom visitors and educational materials including incompetent cherry blossom spirits, a legendary nightmare-eating tapir, and a fourth-dimensional camera that breeches alternate realities.

As a child Sakura Mamiya mysteriously disappeared in the woods behind her grandma's home. She returned whole and healthy, but since then she has had the power to see ghosts. Now a teenager, she just wishes the ghosts would leave her alone! At school, the desk next to Sakura's has been empty since the start of the school year, then one day her always-absent classmate shows up, and he's far more than what he seems!

[From Viz]: Travel into Japan's nuttiest apartment house and meet its volatile inhabitants: Kyoko, the beautiful and mysterious new apartment manager; Yusaku, the exam-addled college student; Mrs. Ichinose, the drunken gossip; Kentaro, her bratty son; Akemi, the boozy bar hostess; and the mooching and peeping Mr. Yotsuya.

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