An ammunition & bomb researcher.
Although he is an artist, he often collaborates with Karashi Mentaiko Gochou on making military&girl-themed doujin books. Their doujinshi, themed on the bombing of Tokyo and bomb disposal operations, are well worth reading.
Japanese name: 山本 権之兵衛 or 山本 權之兵衞 (Yamamoto Gonnohyoue)
The other name: ＡＰＨＥ
Solo circle name & pixiv nickname: たまや (Tamaya)
Joint circle name: 山本部隊試作班 (Yamamoto Butai Shisaku Han) (circle partner: Karashi Mentaiko Gochou)
https://www.pixiv.net/users/828156
https://www.pixiv.net/stacc/sawarabi11
https://twitter.com/tamaya8901
https://twitter.com/intent/user?user_id=1640547860
https://seiga.nicovideo.jp/user/illust/5222937
http://www.nicovideo.jp/mylist/23513649
https://www.nicovideo.jp/user/5222937
https://pawoo.net/@tamaya
https://pawoo.net/web/accounts/53606
https://sketch.pixiv.net/@sawarabi11
http://c10085364.circle.ms/oc/CircleProfile.aspx
http://c10085365.circle.ms/oc/CircleProfile.aspx
http://www.doujinshi.org/browse/circle/42098/