Look here, lonely excalibur boy:
---Lonely: outcast, both parents are dead, has no companion
---Excalibur: Excalibur is a famous sword, hence unicorn. Excalibur belonged to a king, meant to reference Paladin.
---boy: gender, also an indication that he is younger than Knox
In the woods that we shared in our very first breath
---Knox and Soren were both born in the Deep Woods
I'd see myself in you, and I'd meet you eye to eye
---Knox and Soren have the same color eyes (and other similarities in appearances)
---They are both the same height and would thus meet eye to eye
Only you've more than twice the noble blood I've ever had
---Both of his parents were leads at some point and noble in personality, Knox only had one parent who was a lead and noble.
You mutt, you lonely excalibur boy
---breed is a mutt