"+Tic Elder Sister" is a comedic manga series written and illustrated by Yomi Sarachi. The story centers around the daily life of Ichii Naoe, a high school student who lives with his two older sisters, Futaba and Mutsuki. Despite their age difference, both sisters exhibit eccentric and childlike behavior, often causing chaos and confusion in Naoe's life. Futaba, the eldest, is a college student with a penchant for mischief and a tendency to act impulsively, while Mutsuki, the middle sister, is a high school senior who is overly affectionate and clingy toward Naoe. Their antics frequently put Naoe in awkward and humorous situations, as he struggles to maintain a semblance of normalcy.

The narrative unfolds through a series of episodic chapters, each highlighting the sisters' quirky personalities and their interactions with Naoe. Futaba often teases and pranks her younger brother, while Mutsuki's overbearing affection borders on obsession, creating a dynamic that is both endearing and exasperating for Naoe. Despite their eccentricities, the sisters genuinely care for Naoe, and their bond as siblings is a recurring theme throughout the series. The humor arises from the stark contrast between the sisters' immature behavior and Naoe's attempts to navigate his daily life with dignity.

Supporting characters, such as Naoe's classmates and friends, occasionally appear, adding further layers to the comedic situations. However, the focus remains primarily on the sibling trio and their unconventional family dynamic. The series balances slapstick comedy with moments of warmth, emphasizing the familial love that underlies the chaos. The lighthearted tone and exaggerated character traits make "+Tic Elder Sister" a straightforward yet entertaining exploration of sibling relationships and the absurdity of everyday life.