The protagonist is called Alex, a poor sap of a stereotypical nerd (not at all based on the author...), and gets thrown into a typical Isekai fantasy world... without any visible power-ups or special abilities whatsoever. In a world full of dangers (including some easily-angered girls with very poor aggression management), Alex must navigate the dangers of "one stupid comment could get you killed" and somehow reach the (preliminary) end of this Visual Novel alive.
Summoned by three girls to serve as their tactician/commander/leader to improve their in-battle performance, Alex needs to overcome his own weaknesses to live up to their expectations.
Will he fail, or is there actually more to him than meets the eye?