Konse dewa, Futago no Ane no Kage to Shite wa Ikimasen

Just before dying, Princess Lillyn learns her perfect twin sister had deceived her all her life. Shocked by the betrayal, she opens her eyes to find she’s returned to childhood. This time, she's determined not to repeat her fate—and with a talking bird warning of ruin, she must fight to stay alive.

(Source: Manta)