beta
There are actually a total of 3 books in the series, which continue the story.
Deadlock, Deadheat & Deadshot & 3 book extras.
"DEADLOCK Series by 英田サキ" https://www.goodreads.com/series/62281-deadlock
They can be bought from:
https://www.cdjapan.co.jp/product/NEOBK-397272