Wings of Io

You touch a willing medium-sized or smaller creature. The creature grows magical wings, the appearance of which is decided by you, and gains a flying speed of 60 feet. This spell lasts forever, and only ends when you either cast it on a new creature, or whenever you decide to dispel it. When the spell ends, the creature falls if it is still aloft. This spell fails if the creature can already fly.

At Higher Levels. When you cast this spell using a spell slot of 8th level or higher, you can target one additional creature for each slot level above 7th. If you try to cast this spell again without any more available spots, the oldest creature you casted this spell on loses their wings, and the most recent gets them instead.