[Porthos would hate to hear this, but: Sebastian also likes to read and learn things. He's read up on a lot, too, but when it comes to health it's... mostly for Ciel's benefit. Consider: Sebastian is a stubborn idot about being vulnerable.
With that said, he casts a look back at Porthos that's somewhere between "/rolls eyes" and "I'm listening?":]
Have you a better solution whilst we are still out here?