His brief reign as a teenager was known for his violent and impulsive acts, including the slaughter of many high-level officials and his sexually immoral behavior.

[4] On 17 February 456,[5] Emperor Xiaowu married He Lingwan (何令婉), a daughter of his official He Yu (何瑀), to Liu Ziye as crown princess.

Upon seeing Emperor Wen's portrait, he commented, "He was also pretty good, but it was unfortunate he lost his head to his son."

[10] Late in 464, Empress Dowager Wang grew extremely ill, and she summoned Emperor Qianfei to see her.

However, initially, actual power was held by Emperor Xiaowu's close associates Dai Faxing (戴法興) and Chao Shangzhi (巢尚之).

In fall 465, Emperor Qianfei ordered Dai to commit suicide and relieved Chao of his posts.

As a result, just 12 days after forcing Dai to commit suicide, Emperor Qianfei personally led the imperial guards to attack and kill Liu Yigong and his four sons.

From this point on, the people that Emperor Qianfei trusted included Yuan Yi, Xu Yuan (徐爰), Shen, his brother Liu Zishang (劉子尚) the Prince of Yuzhang, and his sister Liu Chuyu the Princess Kuaiji.

[citation needed] In an action that was considered highly immoral at the time, upon Princess Chuyu's pronouncement that it was unfair that Emperor Qianfei could have thousands of concubines but she could only have one husband, Emperor Qianfei selected 30 handsome young men and gave them to her to serve as her lovers.

He had been carrying on an incestuous relationship with his aunt Liu Yingmei (劉英媚) the Princess Xincai, and, resolved to keep her as a concubine, killed a lady-in-waiting and delivered her body to Liu Yingmei's husband He Mai (何邁, who was also his brother-in-law), informing him that his wife had died.

Meanwhile, Emperor Qianfei created Grand Empress Dowager Lu Huinan's niece Lady Lu as empress on 16 December 465[15] Emperor Qianfei was very suspicious of his uncles—that they would rebel against him—so he gathered them in Jiankang and put them under house arrest in his palace.

[16] Fearful that he would be assassinated, Emperor Qianfei entrusted the defense of the palace to a number of fierce warriors, including Zong Yue (宗越), Tan Jin (譚金), Tong Taiyi (童太一), and Shen Youzhi.

He therefore used the He Mai plot as an excuse, sending his attendant Zhu Jingyun (朱景雲) to deliver poison to Liu Zixun to force him to commit suicide, but as Zhu approached Liu Zixun's defense post at Xunyang (尋陽, in modern Jiujiang, Jiangxi), he intentionally slowed down and leaked the news.

When his aunt Princess Dowager Jiang of Nanping (the wife of his deceased uncle Liu Shuo (劉鑠)) refused, he had her whipped.

That night, he dreamed of a woman cursing him, "You are so violent and immoral that you will not live to see the wheat harvest next year."