The yokai graveyard was a place one could enter but never leave. When Inuyasha had taken Tessaiga from his father's remains, he had only been able to escape because the Black Pearl serving as the passage had left him a way out. That had been the Dog General's request to Hōsenki, a provision to let his son retrieve Tessaiga. Once Tessaiga had been taken, the Black Pearl naturally lost its function as a medium and fused completely with Inuyasha's right eye.
This time, Inuyasha and the others had followed Naraku there through a creature from that world, the bird yokai Iron Rooster, traveling along a river formed from its blood. Once the blood ran dry, the river vanished, and the passage between the two worlds closed. Naraku and Yan Luo, who had followed him, had come prepared. Naraku could return through his incarnations in the human world; Kanna and Kagura were his natural anchors there. Yan Luo, meanwhile, had left some Four Souls Shards in the human world. Through her connection to the Shikon Jewel, she could naturally return to the Mortal World as well.
In other words, only Inuyasha and his companions had come to the boundary between the two worlds without any preparation at all. They had no way to return to the human world and might even remain trapped there forever...
Just then, Myoga, who had accompanied Inuyasha and the others to the graveyard, noticed Sesshomaru and Han heading toward the gate to the Otherworld.
"Master Inuyasha, hurry and follow Master Sesshomaru! Hurry!" Myoga urged.
"What?" Inuyasha froze, holding Kagome in his arms.
"Only Master Sesshomaru can open the stone gate between the two worlds. He must have come here through that gate to the Otherworld. As long as we follow him, we can get back through