Gigguku
Ryota spends years staring upward for proof that impossible things exist. Then Neko transfers into his class looking exactly like a girl he knew in childhood. She also brings unusual powers and a laboratory escape into the astronomy club, making the quiet school setting feel suddenly fragile.
Father's Basement
A mysterious lookalike can become cheap melodrama, especially when the resemblance is tied to an unresolved childhood promise. The laboratory escape gives the setup firmer pressure. Neko is not merely a reminder of Ryota's past. She arrives with unusual abilities and a reason to avoid outside attention.