Biomega
"Zoichi Kanoe plunges into the depths of 9JO--an island city in the middle of the Pacific Ocean--in search of Eon Green, a girl with the power to transmute the N5S virus. He's not the only one looking for her, though... Agents of the Public Health Service's Compulsory Execution Unit are also in hot pursuit. Zoichi and his transhuman allies have no time to waste; the countdown to the zombie apocalypse has begun!" -- from publisher's web site.