I think there was no such a thing as boding in a first timeline based on novled. In a second or third timeline bonding is present.
U will see in the third timeline he's bonded since the first timeline
You should check the manhwa s1. When his cruel to aeroc the imprinting shows itself with his purple eyes…
Chap 21 when he found Aeroc trying to kill himself in the cabin, his eyes were purple. When he told Aeroc to die the same way as Raphael.. again it was purple.
It was established early on. He was so obsessed with Aeroc to the point he married a substitute, he then used Raphael to antagonize him, and then used Raphael’s death to have him. The focal point of his plan was to turn him into an omega and impregnate him. The years he’s been obsessing and planning everything and finally executing it was the hatchet. It’s ironic that it was really Clough who put himself in that situation ╮(￣▽￣)╭
Ok I hate him specially in first time line but remember this he's so fuckin unstable because of his bonded partner is actually dead the mother of the children not Raphael so in omegaverse losing your mate is like the worse it drives u insane . Still a dick move he's an asshole