Theo was stunned.

A hidden feature...?

He had come to realize the value of Gluttony over the last few months. He could turn knowledge into proficiency by eating magic books, and rare artifacts into skills. He even had a trump card in Memorize to store magic for later use. If an artifact could replicate even one of Gluttony’s abilities, it would instantly become a national treasure of a nation. But now Gluttony was offering another function? This was overwhelming.

- It seems like it is appetizing.

Theo nodded. “I won’t deny that, but what’s the catch?”

- No catch, I just want to help my user grow quickly.

Gluttony huffed before continuing to speak.

- The problem is the quality of the food. The only Rare books you’ve fed me are [Ballistics Magic] and [Introduction to Elemental Magic]. Don’t just feed me common rabble.

Theo frowned thoughtfully. “The quality of the food…?”

- You might think I am greedy, but doesn’t it benefit you as well?

Theo certainly knew the benefits of eating a Rare magic book. However, there was a limit to...