James-Him by far. He said he loved you after the third month of school while you and Lucius were dating in first year.

Sirius-Him. He said it when he asked you out.

Remus-You. After a while of dating, you told him you loved him when he was saying about his little furry problem would break you and him up which you denied.

Severus-You. You knew you loved him but it took a while to tell him. You told him while he was asleep one night after he was shaking so bad from being terrified.