Welcome Party
Migi and Dali have been fully accepted as members of the Sonoyama family. They behave just like real parent and child, but the twins notice that Mom and Dad are acting somewhat distant. Suspecting that the Sonoyama couple might be hiding something, the two discreetly begin to search the house and stumble upon an unexpected secret of the couple. Migi and Dali are shocked, wondering if they have been deceived. However, determined not to let things end this way, they execute a plan to retaliate against the Sonoyamas.
Aired 09/10/2023EP 2 - Welcome Party

Migi&Dali
After finally adopting a child, the Sonoyamas were unprepared for the mystery that would soon unravel. Hitori seems to be the perfect son for his loving parents. He's handsome, intelligent, and grateful for his new lavish life—but he has a dark secret. Hitori is actually the twins Migi and Dali pretending to be one boy. And they have a terrifying motive behind their hidden identity.
(Source: Crunchyroll)