Nanatsu No Taizai: Gozel

Ever wonder why Meliodas doesn't use his FULL POWER? Well there's a pretty good explanation for that. We know that the elders have kept his powers hidden and only when Meliodas passes the test he could get them back. Yeah, well he did get them back. But did you ever wonder why he hardly uses his full power?
Well what would you say if it involved a blonde lady? Someone Meliodas knows. Someone he trusts. Someone he is protecting. Someone he kept a secret even away from his comrades? Another question for you to know....
What's her relationship with Meliodas??? Since they act so so so close together, much closer than Elizabeth. Well better read this to find out.