I hate that in Sky 1 and 2, Agate and Tita develop a nice, positive, younger sister and older sibling dynamic; and then in future games, the fan-standins in the world push this needlessly, uh…”mature” relationship.

She just wanted a sibling because she was an only child, dudes. Some people just cannot feel out dad/daughter or brother/sister relationships without the standard anime incest crowd.

At least the first instance of that unfortunate trend in the game had some reasonable basis for it (same age, no relation, meeting just before puberty)