Weird Billboards in New York: 'Gift="Demon Slayers"' ?

On a trip to NY recently, I saw a few billboards with strange things written on them. Clearly handpainted, sayings included 'Gift = "Demon Slayers",' 'No Fear Rambo,' 'Bless Yourself,' and 'Papa I love to kill darkness,' among others. Style suggests all done by same person/group of people. Just wondering if anybody knew what these were or what they meant, if it's a gang thing, a reference, or what. Thanks!