Second best, until you

Harry Potter - J. K. Rowling
F/F
M/M
G
Second best, until you

à mon amour, mon soleil.
Sache que je t'aimerai toujours même si ton cœur appartient à un autre, mais je ne peux pas être juste un second choix, une solution de repli.
Je pensais que je pouvais, j'ai toujours été avec Sirius mais j'en suis venu à vraiment m'occuper de toi comme je ne le fais pour personne d'autre.
Avec ton nouvel amour plus brillant, ma capacité à rester dans l'ombre est perdue. Sache que je prendrai toujours soin de toi comme Icarus pour le soleil.
aime toujours le vôtre RAB, au revoir

Tears filled Regulus' eyes as he wrote, clouding his vision, but he refused to let them fall, he wouldn’t let his emotions get the better of him, this was for his own and James' good. He knew that sooner or later someone would find out be it his parents, Voldemort, bellatrix, narcissa, someone would discover their secret and use James to get to him. This was the only way. Regulus knew this from the start. Yet he still selfishly, foolishly let himself fall for James. His smile, his laugh, his heart, the way he looked at Regulus as though he was his entire world, his energetic bubbly personality in public and the shy quiet vulnerable way he acted when it was just the two of them up in the astronomy tower, regulus was so utterly in love with James Potter.
Hah. In love. With James fucking Potter, that's a thought. James potter the most arrogant prick to ever walk the halls of Hogwarts.
James Fleamonte Potter, the boy who had taken away the one thing, the one person, Regulus had ever truly loved, needed and cared for, the boy who replaced him as Sirius’ brother.
James Potter, the light and love of Regulus's life.
Honestly how could he have been so stupid as to fall for the one person he could never have? When did this even happen?
Was it when James had smiled that big goofy smile at him while Regulus helped him with his Potions work?
Or when Regulus had found him at the top of the astronomy tower after curfew and James had simply asked if he wanted to join him?
Or later that night when James had wordlessly wrapped his arm and the blanket he had on around Regulus when he noticed Regulus shivering?
Or was it the first time they met one the train before Regulus's first year when James' eyes lit up when Sirius introduced the two of them and smiled at him making him feel as though he was lying in a field of flowers on a warm summer's day?