Harry Potter and the Obscurus

Overwhelmed by the final straw in his agonizing life, Mo Ran, after taking his own life, unexpectedly transmigrates to the magical world of Harry Potter. However, unlike typical soul transmigration, Mo Ran's consciousness merely attaches itself to Harry's body; he doesn't immediately become the protagonist of the story. How will Mo Ran survive this disastrous start? How will the Harry Potter story change as a result? No system, no cheat codes, only the purest form of magic...