Whenever the Killer reads your Aura and for the same duration as they do so, Object of Obsession activates:

The Killers Aura is revealed to you.
Increases your Action speeds in Repairing, Healing, and Cleansing by 2/4/6 percent.
If you are the Obsession, your Aura is automatically revealed to the Killer for 3 seconds every 30 seconds.

Increases the odds of becoming the Killers initial Obsession by +100 percent.
The Killer can only be obsessed with Survivor at a time.

Whenever another Survivor finishes healing you, Teamwork: Collective Stealth activates and both you and the Survivor who healed you benefit from the following effect:

Suppresses your Scratch Marks for as long as you stay within 12 metres of one another or one of you loses a Health State.
Teamwork: Collective Stealth has a cool-down of 180/160/140 seconds.

Survivors can only be affected by one instance of Teamwork: Collective Stealth at a time.

While repairing a Generator, its Aura is revealed in yellow to all other Survivors located within 32 metres.
If the Killer downs a Survivor while you are repairing a Generator, you see the Auras of all other Survivors for 8/9/10 seconds.

In your countless years in The Fog, you have seen it all, and when you are focused, you can remember most of it too. Succeeding a Great Skill Check while repairing a Generator reveals the Killers Aura to you for 4/5/6 seconds.