Book series about an orphan named Colin who fights demons for a council of mages

It was a book about a male lead young adult.
It started off at a school and I believe his name was Colin but I could be wrong.
He is a mage or has powers.
He goes to a academy of sorts and learns to be a mage but also he tries to be a fighter at the same time.
It has demons or aliens maybe a cross of with otherdimensional demons.
He is adopted and at the end of the first book when they are having a large scale fight he almost dies.
I read this around 2-3 years ago from Kindle for free.
At the end there is a council of mages where he girlfriend kills them due to them not sending reinforcements when they were fighting demons which resulted in the main character almost suiciding and going into a sort of magic coma.
Four books in this series, first book is about the academy of magic where he is clever and creates a lot of spells and improves on others, in this book he also goes onto a mission and goes to another state.
Has a girlfriend who he was friends with in the first book but get together in the second, she almost dies when humans who are working with the demons try to kill her but the main character saves her , he jumps out of a plane and kills them. Demons turn up and he lets them go.
His mother was killed when demons invaded and father goes mad and kills a full nest.
Main character has some demon blood.