Alice didn't mind telling him about her ability, so she told him.
Since she received it, she has been excited about it. It is an amazing ability. Plus, the extra 10% it grants her for assassinating people with over 10,000 power is amazing.
If she thought that was 10% more permanent power she would get from assassinating someone so powerful, wouldn't she become immensely powerful on a battlefield? Just imagining being in front of a large army, murdering people left and right as her power slowly increased, made her feel bloodthirsty, a feeling she couldn't control.
As she recounted all this, Matt noticed that her personality was changing in some way or another.
Her bloodlust was now so evident that it made her eyes sparkle, although she herself hadn't noticed it.
