Full Metal Panic

Tells the same story as Full Metal Panic Second Raid and is as such, also based on the novels The End Of Day By Day. Leaving off after the original series, this series tells of Sousuke and Mithril as they fight Amalgam. Like the original series, but both sides have gotten a bit more aggressive...

Sagara Sousuke isn't your typical high school student. He reads military enthusiast magazines; he responds to questions with "affirmative;" he brings grenades to school in his bag. Though everyone at school takes him for a hopeless military geek, Chidori Kaname thinks there might be something more to him. When their plane is hijacked in the middle of a field trip, Kaname's instincts will prove correct: Sousuke is an elite, mech-piloting mercenary... and he's here to protect her! (Source: J-Novel Club)

Tetsuro Kasahara manga adaptation of Shouji Gatou eponymous novel. *Note: This adaptation interrupted publication after a disagreement between the original novel author and the artist of the manga version over Gatou's disparaging comments of Swedish environmental activist Greta Thunberg, leading Kasahara to claim he will no longer promote Full Metal Panic! Zero nor draw any continuation, and will instead donate any profits from the manga to environmental groups.*