You do do stuff right? Idk I'm tired and I think you do, so take this you don't get a choice, Danny somehow managing to be mistaken for 2 different non human creatures while still somehow not being known as a ghost. How you ask? Well he had to get ecto somehow, and it just happens that, other than using the thermos to collect it, he can get ecto from blood, and Jason happens to be both high in ecto and down to flirt with this presumed vampire twink. And for the other? Well he had to stay somewhere, and his obsession called for the void of space, but he couldn't do that, so he gave it the next best thing, the deep void of the water, it's not his fault his form naturally shifted to more sea like, and it certainly isn't his fault that Tim was nosey while also being lonely enough his core instinctively tried to help the unparented child and he subconsciously accepted!
Long story short Danny has been staying in the harbor/bay which got the attention of Tim, who was persistent and ended up possibly unknowingly core bonding with Danny, so he if fraide now, he is kid, but during the night, Danny has been leaving the harbor to get ecto and Jason just happens to have a surplus of the stuff while being completely ready and willing to act out some crappy vampire romance with this dude and oops Danny got a hot boyfriend now. Somehow, Bruce doesn't know what Danny in either way, likely due to the severe interference from Jason and mostly Tim to make sure he never hears of it.
Unusual problems require unusual solutions
Dc x dp, dead on main
....
Danny core ached with hunger. His open wounds from his escape left him trapped as Phantom, body instinctively knowing that turning back was a death sentence. It only compounds his problem though, core unable to go dormant to save what little energy he has left.
Danny came to Gotham because he had hoped to feed and heal on the unusulually concentrated ambient ecto, but it was so impure his body refused to absorb it. Out of desperation, he goes into the polluted waters of the harbor, hoping at least some ecto from the waters would absorb through his still open wounds. It kinda works. He's still hungry but he won't starve to end if he stays in the bay.
As a distraction, Danny swims, exploring the bay and it's network of underground caves. Trash he thinks he can use goes to a small cavern that he's claimed for himself. Countless corpses and bits of human are bundled in makeshift shrouds and carefully buried under piles of small rocks. It's not much, but at least it's more of a grave than being dumped into the polluted waters like trash.
Over time Danny's body changes. His Hazmat suit tightens and fuses to his nearly skeletal body, becoming sleek, scales that shimmer with the color of oil slick in the right light. Shear ghostly fins flow from his forearms. His hands become webbed. Finally his tapered off flying form becomes a long scaley tail, slightly flattened at the end to aid propulsion in the waters.
Danny floats beneath the surface, invisibly watching a dock worker. The worker had cut himself on something, a few drops of blood sinking into the water and drawing him in with the mouthwatering scent of ectoplasm laced blood.
Danny's humming some half remembered tune, it projects bone deep tiredness and the feeling of pure safety. He just wants a little taste, to see if it tastes as good as it smells, nothing more.
The worker collapses, falling into the water and pulled away to Danny's hideout before anyone can react. Danny tilts the man's head to the side, feeling the clam pulse.
The bite goes deeper than intended, sweet ecto rich blood gulped down greedily. Danny starts at the skipping pulse, horrified. He seals the wounds with some ice, rushing to shove the man back on the docks before he tucks back into his cave. His core still feels starved, but he has ecto reserves again!
....
Notes
I know you requested Jason and Tim, but I feel like this is a good start. I'm kinda into this idea, but no guarantees.
