Originally Posted by
Sj
Okay so my interpretation of the KR Nisekoi was way off (I haven't really spoken/read it in a long time)
Nisekoi 222 - Summary
Chitoge came up with the idea to promise to marry Raku. Yui somehow found a way to have someone manufacture the locket and keys (only one actually works, the "princess key.") Chitoge and Marika argued over which of them it should be, and asked Raku to pick between them. Raku chose Chitoge (Marikafags btfo) because of her hair making her more feminine. Kosaki is watching all of this from the back like the beta fuck she is while holding the picture book that Raku altered for Haru (Best Onodera). As she slips away, the last page falls out.
Later Raku finds Kosaki at the rock with the book. He hurt himself (the scar) and Kosaki was doing anime grill stuff by putting the band-aid on him and asking him if he really liked Chitoge. Raku says he likes her but not in the way he wants to marry her and the girl he really likes is Kosaki. Raku says he wants to tell Chitoge but Kosaki stops him because she said it seemed like Chitoge was really happy that he had picked her earlier. Chitoge had actually heard the entire thing as she had found the page Kosaki dropped and followed her to give it back to her.
Yui shows up with the keys and hands them out to the girls and makes sure that Chitoge gets the locket and the princess key. When she goes to give the locket to Raku, she also trades keys with Kosaki, meaning Kosaki is the holder of the key that fits the locket. Chitoge then makes a promise with Raku, meaning Chitoge is the promise girl. She makes Raku promise to marry Kosaki and take care of her so they can all get together again in the future.
tl;dr - kosaki's key fits but only because she trade chitoge, chitoge was promise girl but promise was to marry kosaki, haru still best girl, marika got btfo because of raku's shit taste