Yuusha no Segare - Volume 2, Chapter 4 − Song of the Starry Sky Part 2

Su Chen lost his sight in an unfortunate, unanticipated encounter. He was unwilling to give up despite suffering one of the most tragic fates possible in the human realm and fought on. Su Chen wants to use his own efforts to create a completely new destiny, both for himself and for mankind!

A filthy, idiotic, hypocritical alcoholic degenerate, known to most as Ricky Freeman, died in a tragic car accident when his lower half was crushed by a drunk driver. Coughing out a bloody mourning for his balls, Ricky finally dies only to wake up in his next life. Reincarnated in the 1920s as a orphaned kid, how will he live in a universe filled to it's brim with cosmic beings-*DING*'Huh?'[Congratulations Host for receiving the Impregnation System]

The more ruthless the Palace is, the more miserable the loser will end up—this he understands. But what he does not understand is, why the brother whom he lived together with peacefully in the past, would so heartlessly humiliate him today. Asking him to beg for mercy, asking him to succumb to his knees, and even… asking him to tactfully entertain him. “Yong Shan, ah, Yong Shan, as of today you are the one who qualifies to succeed as a Crown Prince, what exactly is it that you want?”

For the past 16 years, Yong Qi’s gaze was never set on him. Despite being twins with his younger brother, Yong Lin, Yong Qi has always been directing his smile and laughter towards Yong Lin, and to him, Yong Qi deliberately alienates him. He does not understand, they have the same features and looks, and he obviously is his brother too, but why won’t he be intimate with him… as if he is humiliating him. “Yong Qi, ah, Yong Qi, why won’t you understand, what I want is very simple…”

- Description from Novelupdates

The second prince has come of age. To celebrate the advent of such an occasion, the search for a suitable bride began. My younger sister was expected to go to the Royal Palace as a candidate. However, despite this, she eloped the day before her departure. I, the older sister she left behind, looked almost exactly like her – so much that we were often mistaken for twins…

One month, right? For just one month, shall I substitute in for my sister?