It was common knowledge that although Emperor Yivenya was considered one of the greatest emperors in the history of the Galactic Empire, she had placed the Void Crown upon her head over her own father's corpse, and had risen to power through civil war. The final selection process was less a "legal procedure" than a formality to make the result look "legal."
Of course, precisely because her crown had been soaked in the blood of countless Imperial soldiers and civilians—and even other Dragon Kings—the empress had plenty of room to reform the government. It was therefore widely agreed that the era of Empress Yivenya's rule was the Empire's most enlightened, tolerant, and culturally vibrant period, hence the name "Age of Blossoms."
Tiroe Shire was the first Imperial prime minister to usher in that age. He was the leader of the Prime Minister's Office, the Lord Keeper of the Privy Council, and a renowned Imperial general during the civil war. He had absolute control over the executive branch, the court, and the military—a true second-in-command of the Empire, second only to one person and above millions.
Of course, if one took certain other rumors into account, Prime Minister Shire had actually been Emperor Yivenya's lover. He might even have been the one on top.
And one more thing: the term "lover" was, to some extent, slander spread by political rivals and foreign enemies. Empress Yivenya had publicly acknowledged her romantic relationship with the prime minister, and him alone.
The empress had at least half a company's worth of other lovers, all of them with names, backgrounds, and scandalous stories of their own, but there was no evidence about any of them that could withstand scrutiny.
In short, if Mr. Keko, the Komina biologist they'd heard about earlier, was a top scientist