
Quick answer — Asami Yaguchi voices Tarlant in Fantastic Children, Frederica Sawyer in Black Lagoon: The Second Barrage, Nakayama in Momo, the Girl God of Death and 2 more characters.
Asami Yaguchi voices Tarlant (Fantastic Children), Frederica Sawyer (Black Lagoon: The Second Barrage), Nakayama (Momo, the Girl God of Death), Yoshibo (Black Lagoon Omake), Eleonore von Wittenburg (Dies irae).
Tarlant is voiced in Japanese by Asami Yaguchi.