On the surface, the line is a romantic invitation. But the choice of the word (to dissolve/blend) is what makes it haunting. Unlike "sharing" or "joining," dissolving implies a permanent change.
She stayed by the window, watching him work into the night. He wasn't painting a memory anymore; he was painting the air between them, thick and heavy with the shared breath of a second chance. tu aake apni saanse mujhme ghol de