Bio-booster Armor Guyver Series by Yoshiki Takaya

When the Guyver, an alien life form, adopted the body of young Sho, it endowed him with super powers, and propelled him into an ongoing war with a secret organization. Now Sho and the girl of his dreams find refuge in a secluded cave, until renegade Hyper-Zoanoid Aptom appears to tell Sho the awful truth about his father's death. When Sho's trauma keeps him from transforming into the Guyver, Aptom performs some unlicensed therapy.

Bio Booster Armor Guyver: Revenge Of Chronos (Viz Graphic Novel) [paperback] Takaya, Yoshiki,Takaya, Yoshiki [Aug 05, 1995]

Vintage children's book

Bio Booster Armor Guyver: Escape From Chronos (Bio-Booster Armor Guyver Series, No 4) [paperback] Takaya, Yoshiki,Takaya, Yoshiki [Sep 05, 1996]

When the Guyver, an alien life form, adopted the body of young Sho, it endowed him with super powers, and propelled him into an ongoing war with a secret organization. Now Sho and the girl of his dreams find refuge in a secluded cave, until renegade Hyper-Zoanoid Aptom appears to tell Sho the awful truth about his father's death. When Sho's trauma keeps him from transforming into the Guyver, Aptom performs some unlicensed therapy.

The Guyver and his friends head straight into the belly of the beast when they hide from Chronos' horde of Hyper-Zoanoids in their own headquarters at Relic Point. But soon they will have to face Alkanphel, the most powerful Zoalord of all!

There's terrible discontent among Chronos' hordes of mutant Hyper-Zoanoids. While Alkanphel and Commander Gyro are duking it out over the ominously named weapon 'The Remover,' Aptom infiltrates Relics Point, Chronos's headquarters and laboratory, to 'absorb' the remaining members of the Hyper-Zoanoid Five, Four, Three, Two, One... Meanwhile, the two Guyvers take their first tentative steps into the powerful organic spaceship at the heart of Relics Point... moreThere's terrible discontent among Chronos' hordes of mutant Hyper-Zoanoids. While Alkanphel and Commander Gyro are duking it out over the ominously named weapon 'The Remover,' Aptom infiltrates Relics Point, Chronos's headquarters and laboratory, to 'absorb' the remaining members of the Hyper-Zoanoid Five, Four, Three, Two, One... Meanwhile, the two Guyvers take their first tentative steps into the powerful organic spaceship at the heart of Relics Point. Will our heroes' plan to use the spaceship to destroy Chronos succeed or blow up in their faces? less