Trafalgar Law has been stuck in the past and is suffering from depression because of the deaths of his mother and younger sister. One day, his father called him and forced him to attend a family gathering in his hometown. He was left with no choice but to obey. There he met this ray of sunshine, a little girl who brought color to his otherwise dull and colourless world.(FemLuffy)

The campus beauty Boa Hancock only sees Luffy as the younger brother she wishes she had, but the boy still insists on marrying her anyway. (Hancock x Luffy x Nami)

In which Law and Katakuri are brothers who are caged by their family tradition of fixed marriage and couldn't be able to marry the one they truly love. (femaleluffyxlaw/katakurixreiju) book cover's not mine, credits to the owner.