Jin's words caught Fugaku by surprise.
"How did you guess? Has your vision already started to deteriorate?" Fugaku asked.
"Not yet, but I can feel how much strain using the Mangekyo Sharingan puts on my eyes. It feels as though I could go blind at any moment.
"At this rate, losing my vision is only a matter of time. I have a rough idea of how much my eyes can take."
Fugaku nodded. "The Mangekyo Sharingan's flaw can indeed cause blindness. If you want immense power, you have to be prepared to lose something in return.
"But I've found a way to solve that problem."
Surprise broke through Jin's calm expression.
"There's a genetic defect in our Mangekyo Sharingan. Every time we use it, we consume a great deal of pupil power.
"And that pupil power is lost permanently. It doesn't recover. Use it too many times, and you naturally go blind."
Jin nodded.
"Come to my house tonight," Fugaku said. "I'll deal with the danger for now."
Jin smiled. "All right."
The day passed. Fugaku returned home early and took a syringe of White Zetsu Cells from his underground laboratory. It would be enough to last Jin a while.
Jin arrived that evening as promised, and the two sat down in the living room.
Fugaku held up the syringe. "These are specially cultivated cells derived from First-Generation Cells. They can replenish the pupil power you use.
"Once they're injected into your body, you'll be able to use the Mangekyo Sharingan without restriction. Pupil power will no longer be your weakness."
Jin nodded without the slightest doubt. If Fugaku had wanted to harm him, he would never have helped him awaken the Mangekyo Sharingan in the first place.
Fugaku handed the White Zetsu Cells to Uchiha Jin. "Inject them now.