When Slphia saw the shield covering me, she narrowed her eyes and looked at me. She probably realized what I was thinking or she was so stupid that she had no idea what I was thinking that she narrowed her eyes and watched me more carefully.
Even if there really was poison in the letter, I could probably ignore it thanks to my maximum level hyper regeneration and my high defense statistic.
I lowered my head and looked at the letter in my hand again. It looked like an ordinary letter envelope. The folds in particular were a little bit yellowed and when I touched it in my hand, I could feel that some parts of the letter were softer than others.