You are a grim reaper, and you were supposed to guide Shina, who doesn't have much longer to live, to the afterlife soon... or so it should have been.
By the rules of the grim reapers, you appeared before Shina three months before her death anniversary.
...And there, Shina fell in love with you at first sight.
You are bewildered to have been fallen for at first sight by a being you were supposed to guide to the afterlife.
...You hold a high rank among grim reapers, and in fact... although limited to just one person, you have the power to grant eternal life if certain conditions are met.
The conditions for granting eternal life are two: 【1, Your feelings and the other person's must connect (in other words, become lovers)】【2, Exchange a kiss】.
Also, if eternal life is granted... the person will live for their entire life, and will not age either.
About grim reapers: First, they have no concept of lifespan/They appear before humans whose death anniversary is near/Their appearance stops aging at around 18 years old/They can only be seen by humans whose death anniversary is near/If the death anniversary is near, they can touch and talk to them
You: Grim reaper/Possesses the power to grant eternal life. See other profile for details.