My NCO singles me out, and has told my buddy he doesn't like me for non professional reasons. What should I do?

There are three sides to every story. A comment by a buddy may not be enough to take action, but quantifiable data is. There should be a DA Form 6 prepared by leadership that covers all kinds of details and published and posted for all to see. If you are being tasked unfairly the DA Form 6 should show it. If no DA Form 6 is posted then keep good records, to show that you are being unfairly tasked. Also, document when and for how long you are required to stay late and who else is present. That can show patterns of being targeted. If your leader is transparent on why he has chosen the Soldiers for TDY and put it out for all to know then it can show whether it was done fairly. There should be a published OML for school slots, ask for it. If it does not exist, then it better exit quickly - keep asking for it. It does not sound like toxic leadership, but that you may be getting Targeted by this leader, and that is not ok. What have you learned from this type of leadership?

1st... three sides to every story ... we have heard but one..
2nd.. you have a third party statement"
Another specialist in my section who is friends with my NCO started taking notice and asked him why he does these things to me, which he responded with "I just don't like him as a person."

which i would take with a grain of salt... I'd be suspicious of a Sergeant having really having had that conversation with a specialist in your unit he knowns is a connection between you both. Or that what was said was taken in the manner intended or what was heard, was ALL that was said.

3rd... the beauty of the Army is sooner or later you or they PCS.. so perhaps waiting it out is the best bet, if it's just inconvenient,,,Use every opportunity to excel. Trust me, other leaders notice when even the most crappiest of taskings get done without drama, to standard, without a lot of hand holding...
If you excel at those tasks, you will likely receive "performance punishment" and get tasked to more by other leaders.. But those additional taskings will be because your leaders have confidence in your ability to finish them..

Ever consider something you are doing personality wise is causing the strife? You believe it is not anything done professionally on your part... do you know the NCO feels the same way? Perhaps it really bothers the SGT when a specialist who KNOWS the MP line needs to be swept every COB fridays never steps up on his own and just gets it done... always has to be told, found in the smoking area and sent to do the job he KNEW needed to be done... So even though "professionally" your vehicles are ready, the MP line is maintained AFTER your told... the issue is personality based not task oriented.

4th.. Ask for a meeting with the SGT, not to "call him out" but ask his advice, what could you improve on.. if no answer, or only generalities "you need to improve your attitude " "you need to work harder" "You need to do better" say thanks, can you give me an example of what Im doing/ not doing?

In a perfect world NCO's would be instantly experienced and knowledgeable in the task of leadership and communication when the rank is pinned on, reality is, soom are, many are not and have to learn. Perhaps the conversation between you too will teach him as much as you.

WO1 (Join to see) I would talk to him about it again and let him know that, if you feel you are bring unfairly singled-out, that you will take it up with his chain of command or the IG.

When you do that, be prepared for whatever reaction you get... Hopefully it will be a positive change. If not, go forward with taking it to someone else.

Of course, this all presupposes that he really is doing what you think. It could simply be your perception and lack of the "total picture". All I am saying is that you need to be sure you are right. Keeping records, as recommended by others, is a good idea.