Zutto issho ni itai ( I want to be with you forever )

Shin, cold and reserved was involved with a car accident when he was in college, That accident resulted to the decease of Hina's parents. Out of Guilt and Pitty Shin's parent took Hina to their house and kept her as an adopted daughter They also arrange Hina and Shin's marriage contract alongside with their last will of testament w/o informing the two. It was suddenly been discussed to them by the family lawyer as Shin's parent died with the plane crash while they're on a vacation a year ago. Let's see how the two will work with this situation being as sister brother relationship to being a couple. As they both tied up on their feelings on fulfilling thier loving parents request w/c is the marriage contract.