Bluebeard was a man who used to marry women and kill them, perpetually.
this poem is about how the Sun is like Bluebeard for it gives light to the night and then kills it every morning.
If he's a red flag then she is colour blind for him.
She's the only obsession for him.
"Love me till the day I die sunflower"
"I Love You Aadi now and forever"