The official Japanese website for the Japanese-Taiwanese collaboration anime adaptation project based on Yanai's Jikken-hin Kazoku: Creatures Family Days manga announced two additional voice cast: Saori Hayami (Ayase Aragaki in Oreimo) as the eldest daughter Ashisu and Daisuke Namikawa (Goemon Ishikawa in Lupin The Third) as the eldest son Suno.

Ashisu: Saori Hayami (Ayase Aragaki in Oreimo)  

Suno: Daisuke Namikawa (Goemon Ishikawa in Lupin The Third)

本日、第二弾メインキャスト発表！&第二弾キービジュアル、 アシス、スノーのキャラデザ画初公開！
アシス役は早見沙織さん、スノー役は浪川大輔さんに決定！
詳しくは、本日発売のコミック@バンチ、アニメ公式サイト、Twitterをチェック！ #jikkenhin https://t.co/jtuUmrLssU pic.twitter.com/re6MnUOtPS

— アニメ 実験品家族 公式アカウント (@jikkenhin) 2018年2月21日

The anime's second key visual is also revealed (via: Mantan Web). 

「実験品家族：テレビアニメの追加キャストに早見沙織、浪川大輔」(February 21, 2018 at 12:00PM) https://t.co/zlE9di5Z5g

— MANTANWEB (@7109mw) 2018年2月21日

The family drama manga follows five brother and sisters whose both parents are mad scientists. Except

the 11-year-old youngest child Tanisu, they are all re-created humans who are different from normal people.

After the arrest of their parents who have hidden them from the public, the five have to figure out how to

live as a normal family in the human society.

The manga has been serialized in Taiwan's web comic site Sun Comics and has been also running in

Shinchosha's Monthly Comic @BUNCH in Japan. The adaptation animated by Big Firebird Cultural Media

and directed by Wei Tianxing is set to premiere in Japan and Taiwan simultaneously in April 2018.

Announced voice cast:

Tanisu: Riho Sugiyama (Urara Suidoubashi in Atom: The Beginning) 

Aisuri: Nanako Mori (Akira Kenjo/Cure Chocolat in Kirakira PreCure a la Mode) 

 Suishi: Yoshiko Ikuta (Lulu Yurigasaki in Yurikuma Arashi) 

1st PV featuring the OP theme song "Early Days" by Rin Akatsuki

Source: TV anime "Jikken-hin Kazoku: Creatures Family Days" official website, Twitter, Mantan Web

©Yanai/日更計画