[X] Lose them, it's not like you care
Really, it's not like such pests are worth your time at all. You call forth your stand and stop time; having The World leap and carry you back home. Your reach the time limit for your time stop and time continues just as you reach the Emiya estate. The worthless dreck that was following you is no doubt confused at to your disappearance, but it is of no consequence.
Now though, you had a interesting gem to investigate. You look upon the blood red gem, holding it up to the sunlight and watching the sun's radiant rays glisten and shine within the jewel...
...Only to just barely move your head out of the way as the gem focuses those rays a hundredfold and releases them in a beam that scorches the ground behind you. You hurriedly move the gem out of the sunlight and begin to ponder what just happened. The gem took in the sun's rays and focused them into a likely lethal attack. Almost like...
Like Jojo's little 'hamon' trick; oh you remember clearly the technique and style that brought forth your first downfall: the way Jonathan managed to replicate the energy of the sun's rays. This gem was clearly related to the practitioners of the stlye, which made it all the better that it was in your hands instead of theirs. Maybe you could research it and discover a way to counter the Hamon, creating an 'anti-ripple' of some sort that could cancel out the original. Like how a positive and negative charge equal out to nothing; your 'Anti-Hamon' and the regular Hamon would cancel each other out, leaving a regular human against the superiority of a vampire.
You would have to use magecraft to create this, obviously; but with Kiritsugu's limited knowledge it was going to be difficult. Clearly, it was time to see if you could find one of the 'Three Families' that held such an investment in Fuyuki and the Holy Grail; surely they would have quite the treasure trove of thaumatrugical knowledge.
You hear the front door open, and see who was coming in. It was none other than Pucci, back from his voyages to obtain what you seek: the Stone Mask that bestowed upon you the gift of vampirism.
You ask your subordinate, "How goes the hunt, Pucci? Have you finally gotten a lead?"
Pucci simply nods and says, "Yes, Dio-sama; I have finally found the probable location of several masks that match the description you have given me."
"One is within the hold of the damned Speedwagon Foundation; it is likely the hardest to obtain, but compared to the other option it is the most stationary. The second is currently in the possession of one 'Touko Aozaki', who is currently residing in Mifune City; though she is know to relocate from time to time as if on the run. The last is in the possession of an auction house that is currently touring the world, spending three years in each country on its route. It's next stop is in Germany, though by the time we reach it the mask may have already been bought by someone else."
"Good; once again you have proven to be my most trustworthy servant Pucci," you tell the priest, praising him, "Only you would be able to bring results on such a rare relic so quickly. We will move when Emiya dies, which by my estimate will be in a matter of months; if not earlier if we...speed up the process."
You give a devilish grin at the end, with Pucci simply smiling reverently in return. Yes, if Emiya proved too stubborn to die quickly, then you'll simply make it go faster like you did with George: it's not like you actually need the pitiful, broken man anymore.
And sure enough, once he returned and proved to not die as the months passed; you sped things up by having Pucci slip poison into him via Whitesnake every night. Even then, the bastard proved too stubborn to die, taking another year to finally kick the bucked; though not before mentioning his stupid 'Hero of Justice' dream and the existence of his daughter with a little manipulation and prodding on your end.
While you were waiting for the fool to die, you were scoping out the two families that were on Fuyuki soil: the Matous and the Tohsakas. Of the two, you believe the Tohsakas have more knowledge that would be helpful in discovering the secrets of the jewel, but the Matous are far easier to manipulate; with a degrading bloodline and little hope to continue on. Desperation is quite easy to take advantage of, especially for one of your talents.
You've even looked into their heirs; the Tohsaka heir seems to have been the little girl you passed after getting the stone. She seems to be angry that such a valuable stone is outside her grasp, wanting to deliver retribution to whoever stole her 'prize' and take it back by any means necessary. Her guardian seems to only bask in her anger and misery, not stopping her foolish quest at all. This will make an alliance difficult; you will be forced to bend the girl to your will, and watch out constantly for rebellion from her. She doesn't seem the type to simply accept someone else taking charge and making her their servant.
The Matou heir is...withdrawn. Empty. And completely vindicates your idea of the family itself being easy to manipulate. Clearly; they need the girl to be completely obedient so that they can rebuild themselves without any semblance of rebellion in their ranks, needing a 'tool' rather than a person to rebuild the family. With the Stone Mask and its offers of immortality, plus the offer of Stands; you have no doubts that you can buy the allegiance of this family with ease. Especially the girl; with the right nudges here and there, she'll become a tool that serves your will over any other.
Your own research on the jewel has borne little fruit; you simply lack the knowledge to delve deeper into its secrets. All you've found is that it's seemingly perfect and can take in and focus the rays of the sun a millionfold. It's simply unreal in terms of how potent a light amplifier it is.
But now, now it was time for you; Dio, to ascend to what you were meant to be. To once again take you place as the deity above the worthless maggots know as humanity, so that you may bend them to you will.
But...which mask shall you go after?
[X] The Speedwagon Foundation's
[X] Touko Aozaki's
[X] The auction tour's
And which family do you think you will subvert to your will?
[X] Tohsaka; their jewelcraft will prove quite useful to your cause
[X] Matou; they are far easier to manipulate and bend to your will
