The Lock

"The guiltier you feel, the bigger that lock gets... In other words, that lock is the "weight of your guilt"."

- Tamami Kobayashi, Chapter 285

The Lock is the Stand of Tamami Kobayashi featured in Diamond is Unbreakable.

Appearance
The Lock appears as a giant U-Shaped Lock hooked onto the target's heart, appearing fused into their chest. As with most Stands, only people with Stand powers can see it. Even the afflicted has no idea it is there.

Tamami can also hold The Lock as a tangible item, as shown when he is called by Rohan Kishibe to confirm that Josuke is cheating in their game of dice.

The Lock is portrayed as being brown in the colored manga, and metallic grey and red in the anime.

Abilities
The Lock is an automatic Stand that has no combat ability whatsoever but perfectly fits Tamami's petty goals. It is odious, but surprisingly dangerous because it can push people into committing suicide.

Guilt Increase
By making someone feel guilt, Tamami can then summon The Lock which appears inside the victim's chest.

Afterward, their guilt is multiplied continuously and can add up with other accusations, represented by The Lock growing bigger and heavier. The Lock will stay indefinitely even if its away from Tamami, until the victim either feels so guilty they commit suicide, Tamami willingly cancels The Lock, or the source of the guilt disappears, usually meaning that the person "absolved" themselves by compensating Tamami with money or they learn that there is nothing to be guilty about. Tamami can trick people into feeling guilty for perceived but false wrongdoings and even lock several people at the same time. On the other hand, Koichi could influence his mother into not feeling guilty anymore, cancelling The Lock at the same time.

Tamami also claims that if someone with The Lock on them attacks him, the damage will be reflected on the attacker, but this is never shown.

Lie detection
The Lock is shown to be capable of detecting dishonesty in a person, as shown during Josuke's cee-lo game against Rohan. Though this power isn't elaborated on in much detail, Tamami explains that The Lock will move if it senses honesty, and stays still if it senses dishonesty.

Gallery
Manga=