Manatsu No Grey Goo 4 (KCDX)

[Machine Translation] Manatsu and his friends meet up with a group of university students at a campsite, but they are attacked by tree-shaped nanomachines! Their only means of attack, citric acid, has also run out...! Their old friend, Kudo, is the source of Grey Goo! Trusting their friend, Manatsu and his friends return to Ibaraki, a place infested with nanomachines, to confirm the truth. On their way to Tsukuba, their hometown and a place of memories with Kudo, they are attacked by tree-shaped nanomachines and flee to a campsite where they find a group of university students left behind. The citric acid that had guarded their surroundings was washed away by the rain, and one of the college students became a casualty as the tree-shaped nanomachines attacked en masse. Manatsu and his friends tried to escape in a camper, but the car was hijacked by the arrogant campground owner...!

キャンプ場で大学生一行と合流した真夏たちは、樹木型ナノマシンに襲撃される！頼みの綱の攻撃手段・クエン酸も切れてしまい…！？旧友である久遠がグレイグーの元凶！？友を信じる真夏たちはその真偽を確かめるため、再びナノマシンがはびこる、茨城へと戻る。久遠との思い出の場所である地元・つくばを目指す途中、樹木型ナノマシンに襲われて逃げ込んだキャンプ場には取り残された大学生たちがいた。周囲をガードしていたクエン酸が雨で流れ落ち、樹木型ナノマシンが大挙して襲い来る中、大学生の一人が犠牲になる。キャンピングカーで逃げようとした真夏たちだったが、傲慢なキャンプ場オーナーに車が乗っ取られてしまい…！？