I cried "grandpa please don't leave me I will be a good child I won't seek revenge but don't leave me please" "hahaha silly grandson, how will grandpa will leave you, grandpa always want to stay with you and I will, thanks to your special soul grandpa can live inside but do you promise that you will live a happy life and won't seek revenge. I don't want to you seek revenge actively and die so I won't be telling you the identity of that person that did all this things, now I will let my consciousness inside that soul of yours so when I see you are strong enough, I will tell you about all those things. Even if my soul is fading now I have to give a gift to you for your birthday. This is your heritage from both side of your family and yours owns too, but I slightly modified it with the help of the consciousness inside you, so it can help you grow, in your journey you will come to know what's the name stone represent, first of all as you see your grandpa become otaku here, so I will give you your heritage in a form that will help you grow and it will grow alongside with you. I don't want you just rely on that power I want you to make that power yours, so as an otaku l am giving you hehehe a 'system' tada"