While alien invaders try to eradicate humanity, Retto discovers that Kirara has closed herself off from the world due to a traumatic experience, and is worried about her.

Retto Enjō joins the HxEros team to fight the Kiseichuu, an alien that feeds on human libido known as H-energy.

Maihime Shirayuk lacks confidence; a Kiseichuu appears at Maihime's school; Sora Tenkuji, aka Hxe Blue, has a secret hobby; Kirara finds out Sora's secret; Sora makes Kirara take part in her antics.

Retto and others head to a nest of Kiseichuus to rescue Kirara who was abducted during a battle.