What an admirable guy, who, when finding himself in a game his little sister nattered on about, wanted to minimize casualties as best he could. Also, I'm assuming he's the Civ/RTS-type, since his priority is forming alliances, even with "villains," to achieve his goals.
Also, Ashley, you're being too subtle, for feth's sake.
@Cumology There are a good number with 2 isekai'd characters like Lady Adelaide and For Certain Reasons, the Villainess Noble Lady Will Live Her Post-Engagement Annulment Life Freely. But this might be the first where the both know that about each other and help each other.