Onee-san ga Shinryakuchuu

After failing his university entrance exams, Toono Ao becomes a ronin, dedicating himself entirely to preparing for the following year's tests. Seeking an environment free from distractions, he moves into a modest apartment conveniently located near his cram school. Though small and unassuming, the space represents his first taste of independence—a quiet sanctuary where he can focus solely on his studies and finally get his academic life back on track. However, his peaceful new routine is abruptly shattered when an intoxicated older woman wanders into his home shortly after he settles in. Despite Ao’s best efforts to establish boundaries, she effortlessly makes herself comfortable, continually invading his personal space and taking advantage of his hospitality. What begins as an unwelcome intrusion gradually blurs the lines between frustration and reluctant acceptance, leaving him questioning whether he truly wants her gone. His humble retreat is no longer his own, as the relentless onee-san has officially launched her invasion.