"Consent" of underaged indivvidual not a mitigating factor for sexual offences

R. v. Bjornson, 2012 ABCA 230, a recent Alberta Court of Appeal decision, holds that the fact an underage complainant was a "willing participation", is not a mitigating factor in a charge of sexual touching :

[11] As for the degree of responsibility of the offender, Bjornson was 22 years of age, a mature adult. He knew that the complainant was only 15. As the adult, Bjornson had the responsibility to ensure that his actions did not cross the line from the legal - friendship - to the illegal - sexual intercourse and fellatio with an underage complainant, no matter how willing she was to engage in that activity.