I'm actually more of a YujiKiri but KiriYuji isn't bad. I favour the prettier looking one to be the Seme. For just general Eugeo and Kirito content look no further than "If you were here" which is also known as the Cake Timeline. Basically it explores what happens if Kirito and Eugeo weren't arrested in the academy and became Integrity Knights.
Another good one is "Distant Journey" which explores more of Eugeo and Kirito's adventures in the gap in trying to get to the Northlangarth Elite Swordsman Academy.
If you can spare a number of shekels, you might be interested in the gameverse too but specifically Alicization Lycoris. There's a LOT of YujiKiri and KiriYuji content there.