In the light novel, they have an antagonistic relationship that is shown between them, with each one of them having his own way of ruling over the school. Manabu is shown to have some worries about the future of the school case Miyabi continues reigning over the school as the 'Student Council President', going as far as to establish an Anti-Nagumo movement.
Honami seems to hold Miyabi in great esteem, thinking that the two of them are quite similar since he started in Class-B and climbed to Class-A, it is also by dint of his involvement that Honami got finally accepted in the student council. That aside, the relation between the two of them, as for now, is quite good, but since Miyabi is a womanizer, it is still unknown of what he thinks of Honami.
After seeing Kiyotaka's performance in the relay race against Manabu, Miyabi became sort of aware of Kiyotaka, but still not thinking of him as a legit threat, it was clearly emphasized in Volume 7.5.