Re Birthday

What happens when an immortal test subject falls for a mortal high school student?what happens when the test subject is on the Run? What happens if the immortal test subject turns the mortal,immortal? What happens when betrayal and sacrifice smacks you in the face?

Len Kagamine died on the day of his birthday in an accident. But what if resurrection were possible? Could a mortal be turned immortal with just a few test runs? Len is on the Run from the scientists who made his body immortal. He's highly unstable though and needed to do a very fatal test to become more stable.

Luka Megurine is a mortal high school student at Vocaloid high school. She lives a normal life until she's kidnapped and is asked for serious help. What could a weak mortal do? Luka is weak and can't fight anyone. But she could turn immortal with just a few......test runs.

How can a mortal and immortal come together as one?