"Ah," Lumi said and then, after a moment, "no. No antibiotics, no blood tests."

Ordinarily, the antibiotics would just be useless to him and the blood tests routine, but Lumi didn't trust Szayel. He didn't trust him not to use it to ascertain the potential weaknesses of Marluxia's attack dog, or to compare it to the rest of them. He was different to the other Ryoka, he didn't want Szayel, of all people, to discover this. It was bad enough that he had identified an elemental weakness in somebody that presented as wholly Non-Elemental, he didn't need the opportunity to create something more directed.