Hachiko's Collar

Origin
Hachiko (10 November, 1923 - 8 March, 1935) was an Akita dog owned by a Japanese college professor. Every day, Hachiko's owner would take a train to work and at the end of each day Hachiko would be waiting at the station to greet his owner. The pair continued this routine until, one day, Hachiko's owner died and never came home. Hachiko stayed, waiting at the train station for his owner who would never arrive until he eventually died there

Effects
When placed around someone's neck, it creates an extreme sense of loyalty in them towards whoever placed the collar on them to the point that they will do whatever that person tells them to