Io E Te by Niccolò Ammaniti

A withdrawn teenage boy fakes a school trip to hide in his apartment building’s basement, intending to be alone, when his troubled older half-sister unexpectedly shows up and forces an uneasy coexistence. Confined together over a few days, their guarded defenses give way as they clash, confess secrets, and reveal vulnerabilities — confronting family fractures, addiction, and loneliness. The enforced intimacy transforms their relationship, forcing both to face fears about identity, dependence, and the possibility of connection.

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