Izaya was reluctant to follow his sisters, even though Shizuo never was one to be bound by rules dictated by society, he would rather not take any unncessary risks. At the same time he knew Shingen enough to be sure staying alone in this island was more dangerous than confronting the blonde.
He was always following the path his brain chose to be the safest, no emotions were taken into account, never.
That's why he finally decided he would follow his sisters in the pursuit of the infamous monster of Ikebukuro.
He also had to admit that he was interested in how the man who claimed to desire peace and hate violence would do in such a bloody game. He was curious, last time he had seen him, before he started to chase Izaya, he was with his brother and he knew he would never leave his brother without a very good reason.
Observing him from afar he alreay knew something was off about him, if he had to say what exactly was the problem he would say Shizuo was too calm.
From there on, the only conclusion he could reach was that Kasuka had been killed. Assumption confirmed by the fact the normally white shirt he always wore was stained with blood.
Izaya wanted to know what happened.
In front of him Mairu and Kururi were chatting about their favourite actor, as usual. He told them to stop as quietly as he could. He had no idea what Shizuo could do now that he had lost his precious little brother.
After a while they saw him starting to dig a hole and slowly put the head in it.
When the twins saw this, they fell into each other's arms and bursted into tears.
Despite all his efforts Izaya couldn't calm them down.
His eyes were locked on Shizuo, ready to start running at the smallest sign of him standing up. However, he did not move an inch. Startled, he suggested to his sisters they should go and pay their respect to Hanejima Yuuhei, that his grave would be a secret only between them and him.
And so they moved and sat beside Shizuo.
Between tears they managed to tell him, "We're sympathizing with you Shizuo-san", to which Kururi continued "Sorry", Mairu going as far as to put a hand on his shoulder.
He slowly turned his head toward them, muttering "Thanks" and set his glance back on the horizon line.
Izaya didn't expect this. While he predicted he would never hurt his sisters he didn't imagine it would be to that extent. Seeing Shizuo like that was almost like seeing him dead. Somehow, Shizuo was acting like a human confronted with the loss of a loved one, and the informant didn't like that.
Slowly stepping out of the forest he advanced toward the blond,
"Shizu-chan?"