Thanks for the chapter!
I find it hard to believe her health is really that bad considering how well off her family is. On the other hand doesn't seem type to miss school for no reason. What I am sure is that she really likes Souta who is an idiot for not considering that she likes him and is flirting/teasing him. After all, the maids being out on an errand or something is unlikely to happen even once, but twice in a row of his visits? Impossible. Only reason the maids were out was Kaichou got word from front desk he was coming up so sent them away to be alone with him. Otherwise considering her poor health there'd be several maids to be able to respond immediately if she collapsed, one or two to hold her up while third and maybe fourth changed her if wanted to change clothes, and at least a pair of maids/bodyguards to prevent her from being kidnapped and held for ransom just for being from a rich family.