Not to hate but, I think the author wanted to add a little bit of MADK to it.

Not even close lol

MADK ended with M becoming so obsessed with J it led to his ultimate downfall 'cause J's whole plan from the jump was to die.

Azure was looking for someone who could give meaning to his life in a sense 'cause living for thousands of years made him completely numb to everything.

MADK, even as a concept, is completely different than BBV. J never falls in love with M and even relishes the pain M feels while he's finally dying, hoping that he feels it for as long as he exists. The only thing they have in common is that there is gore and a deeper psychological theme in them outside of "I love you uwu."