Ageha O Ou Monotachi

In the year 2039 Ageha Shiraishi is sentenced to death after strong evidence found her guilty of killing her four roomates. She claims she is innocent but no one will listen to the words of an well versed actress. Ageha is sent to Talsis Prison where she meets the prison guard, Kenzaki Kyousuke, who gets the feeling she may actually be innocent. Before the day is done Ageha escapes prison and Kenzaki gets fired for incompetence. Ten years later Kenzaki is on the hunt for the mysterious Ageha.
From Baka-Updates:
Ageha Shiraishi has been sentenced to death as she was suspected of murdering her four roommates. In her prison cell as she awaits her execution, she tells her warden, Kyousuke, that she is innocent and that she did not commit murder. Kyousuke does some research, but finds that she is still guilty. Upon his return, he finds his superior tied up and stripped. After setting her free, he finds out that he has been tricked, and it was Ageha in disguise. He is surprised to find Ageha can impersonate anyone to the finest detail, whether it be hair color, habits, or even voice. Ageha becomes the first fugitive of the Talsis Prison and she declares that she will find the real culprit. Kyousuke now only has one clue, which is “the Ageha” (swallowtail butterfly) tattoo on Ageha’s back. The chase between the characters involved begins as they move to grasp the truth!