A Bunch of Thugs
Saruhiko joined Homra because his own power wasn't enough to change the world. He thought that by joining with Yata Misaki they would be able to become stronger but instead the two of them just grew apart.
Aside from Tatara Totuka, Saruhiko was unable to connect with most members of Homra. He had a semi-professional relationship with Izumo Kusanagi who was looking to Saruhiko as his successor. He would often ask Saruhiko to accompany him on Homra business in an effort to train him in the business aspects of Homra. He thought highly of him and Saruhiko was almost regretful about leaving Homra without telling him.
"He has a sharp mind, a strong business sense, and guts to boot. But best it his ability to not get swayed by the opinions of those around him and think fairly." - Izumo Kusanagi
Saruhiko never thought of Mikoto Suoh the way the rest of Homra did. Misaki and many of the other members looked up to him to the point of blinding themselves to Mikoto's flaws. That doesn't mean that he didn't respect his first king. He thought highly of him but that was overshadowed by the fear he had for his powers.
His fear of Mikoto escalated when he found himself unable to fit in. He began to wonder if his presence in Homra was just a mistake because Mikoto didn't seem to like him. In reality, Mikoto doesn't outwardly show much emotion but to Saruhiko that was a sign that Mikoto made a mistake in allowing him to join. This is true in a way. Saruhiko is ill-suited for the red clan. He is the only one hurt by Mikoto's flames and is often unable to withstand them even after joining Homra. Beyond that though Saruhiko is at odds with the idea that he should be family because he doesn't understand how family is supposed to act.
Mikoto does show interest in Saruhiko although Saruhiko never sees it. He goes to his apartment when he senses Saruhiko in danger and makes sure that Saruhiko's decision to leave isn't being forced by Munakata. Overall, though Saruhiko is too different from the members of Homra which allows him to fit in with Scepter 4.