Through the power of the Eternal Mangekyō Sharingan, you gain the ability to place an opponent in a genjutsu through eye contact. This genjutsu makes the victim believe you to be their greatest ally who was always a part of their life. You also gain these memories, but you know they're fake. Said victim always sees you in a good light, and even if this genjutsu is dispelled, they keep the fake memories.
Project V17/Powers/Shardless/Eternal Mangekyō Sharingan Abilities/Mangekyō: Kamimusubi
From Worm CYOA Wiki
Amenotokotachi
Your power has advanced to an entirely new level, no longer are you limited to simply rewriting another’s memories but you can now rewrite history itself. Similar to the Infinite Tsukuyomi this technique is utilized on a worldwide scale to rewrite history in a manner of your choosing. With this technique you could rewrite your own place in history, take the place of anyone and make them an outcast, write yourself into the very fabric of a world’s story, or do this for another. As this is a true change, this doesn’t simply rewrite memories but will act as a retroactive change. This also increases the range of all your other abilities, granting you the ability to cast and maintain any of abilities on at least a global scale.