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Original Description:
 
Another Head-canon illustration around my AU [Alternate Universe] with further story and emotional moments with Twilight Sparkle and Everlight Everlasting! <33  
This time, it’s a sad, sad one…Where we’ll see Luster Dawn’s last moments…  
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HEADCANON
 
A head-canon or alternate universe, if you wish; a time long after Princess Twilight has been crowned the ruler of Equestria when Princess Celestia and Luna had retired, Twilight was now responsible along with her best friends to take care of the land.  
Yet as time when on and her appearance never changed compared to everyone else, is it possibly that other then being a Princess and an Alicorn; maybe she was more different then she thought. Immortality made her stand out among any-pony else. And with immortality, comes great happiness and great grieve…
 
Which comes to this shriveled moment; likely a sight and feeling Princess Celestia felt in her time of taking students and pupils underneath her wing. Out of all the students she taught, only one that she personally taught gained the availability of immorality through Alicornization. Twilight Sparkle taking responsible over Celestia’s ‘School of Magic’, she gathered further interest and sympathy towards one pupil that needed her the most in learning what the magic of friendship can mean.  
And truly, she was a brilliant teacher. Perhaps the best. But unfortunately to her own feelings, Luster Dawn didn’t have the open opportunities that she did even if she secretly tried. Luster Dawn was grateful, happy, and overflowed with joy at her mentor’s attention and love.  
That’s all she ever wanted and Princess Twilight Sparkle gave her more then she could have ever hoped. Even until the very end when her skin wrinkles and her mane lightened, Twilight Sparkle was at her side.