Comments of chapter undefined of Demon Lord Shapeshifting System

The DNA 'runs out' because it gets absorbed, so that means he can't use the skill from that DNA once he had fully absorbed it. But he doesn't lose the skill 'forever'. If he absorbs more DNA from the same person or someone who has the same skill, he regains that skill. For example he absorbs Mermaid A's DNA so he gains Mermaid skill. The amount of Mermaid A's DNA he consumed has a time limit of 30 days. After 30 days he loses the skill. But there comes Mermaid B, and he absorbs Mermaid B's DNA so he gains the Mermaid skill again.