If this shelf is for soulmates then you might as well fill it up with stories about werewolves…
Alot of werewolf stories follow similar facts about mythical creatures, the biggest one which most werewolf stories are based on are the idea of a “mate” where every werewolf was made to be only one half and that every half has another wolf which is perfect for them, and the “moon goddess” the god of the werewolves decides who is destined to be mates…
Both mates feel an undeniable tension towards each other and being without the other is practically unbearable… So mates is the wolf version of a human soulmate…
Hence why this shelf would suit almost every werewolf story.
Examples:
The wolf within
Dirty blood
The legendary White wolf
Bitten