This achievement is for absorbing a yellow soul from the group of carp fish found in the east area.
Once you have access to the "
East Area" you will have to advance through a large tower which requires a lvl 3 green gem in order to enter and exit. Once you exit this tower you will be on the bank of a small pond walk to the edge to find a small group of carp swimming. Hold your absorb button down for about 15 - 30 seconds and a yellow soul will emerge granting you the achievement.
**Video Guide, Starts at 00:12**