Review as of Chapter 68
ML - yandere made somewhat tolerable because the FL isn't helpless and actively frustrates the yandere tendencies
FL - physically strong, intelligent but not wise, vulgar and unapologetic about it (I like that)
Frankly I don't read this for the romance. I read this for the brother-sister shenanigans which I find endlessly entertaining. FL/side character relationships like other knights and her maid are also pretty good.
Disgruntled chibis are great. Main drawings as mentioned earlier rely heavily on headshots. Backgrounds are meh.
My recommendation: don't read this drawn in by the early sex and hoping for lots of steamy interactions and tension. The people who want read this are those that want a heroine that is easily annoyed and not afraid to swear about it, comedic interactions with most of the people around her, including deliberate frustration of a possessive male lead.