I'm confused on something.
I get why glasses boy has multiple talents, given that he's a talent thief and taking them from a dying returner lets him keep thim for good.
But why does Nightingale get to have a fuckton of them?
First, it's always possible for a returner to have multiple talents. For example, Neumann, Caesar, Gale, etc.
Now about the Nine Tailed Fox (using Gale's name currently), she has 2 original abilities.
The first one is Monster's Hide allowing her to steal someone's life and storing them as her own. The max number is 9 times, and it's likely that the life stolen also includes the abilities of the original returners. It's also likely that the skill to control the bandage comes from this ability
The second one is Killing Mark, the ability to create and manipulate crystals that destroy anything they touch. It's also possible only someone killed by Killing Mark would become the life for Monster's Hide. Same mechanism for Touya's 2 abilities, one to steal and one to use.