He is not tired of pursuing him; on the contrary, Luke loves chasing Asch, through the
fields of Rugnica, through the cracked pavement of Belkend and perhaps even beyond the world one can only see with their eyes. He is often asked "Why do you follow him with ardor?", and
while he never provides the exact same response twice, beyond the excess words of denying
any and all affection and other tender feelings, Luke finds himself always tacking on
a variation of "Because he needs me too," at the end of his long-winded and often stutter-ridden answers.
There is no other explanation in his dull, lifeless-but-not-quite green eyes. He knew,
deep within his maturing self somewhere, that everyone must have thought in some way or another "Surely, there is someone else more worth living for?". There was, Luke knew, but strange days had only just begun and there was very little time for him to waste considering what-ifs and what-could-bes. There was someone who needed him now; a man who, despite being able to overcome the most harrowing of childhood's due to the strength found within his pride, was incredibly weak in his own way, and there was no denying it.
Inside, he wishes for his original's love and acceptance, and that is why he often
finds himself running almost blindly forward at the mere mention of his name. But simply stopping on a cracked road and praying for the other to one day find value in him and backtrack his lifelong journey all for him is impossible, for the Light of the Sacred Flame knows that the other just doesn't have the time. So instead, Luke tells himself adamantly, he will continue to chase after his original because it is not in any way as foolish as anyone else may think. There will come the day when he will have enough of the wisdom and sense one can only obtain from living more than a meager seven sheltered years, to raise his hands in the air towards the limitless, futural sky, because he knows that, like a shooting star or a lonely bird, Asch will fall out of that sky and he will need somewhere safe to land.