Hentai Ouji to Warawanai Neko.

Synopsis

While a sick Tsukasa is being treated by the younger Yōto, the young Tsukushi, along with Tsukiko, agrees to visit their mother once again after Yōto persuades them. At the mansion, the young Tsukushi and Tsukiko wear the clothes their mother made by hand. Knowing that their mother loved them, the young Tsukushi laments over wanting to have memories with her mother. The younger Yōto reprimands Tsukushi, but nonetheless, gives her his precious memories with Tsukasa for their sake by wishing to the cat god, resulting in the current Yōto forgetting all about meeting the Tsutsukakushis and Emi in the past. Meanwhile, Yōto and Tsukiko return to the present. After heading back to the mansion, Tsukushi decides on not going to Italy and afterwards, Yōto and Tsukiko share a kiss. Days later, Yōto, along with Tsukiko, Tsukushi, Azusa, Emi, and Mai have fun at an amusement park.

(Source: Wikipedia)