Goodbye! I'm Being Reincarnated!, Volume 1 (Goodbye! I'm Being Reincarnated! #1-3)

High-school teen Yuya Kamigasaki lives a perfectly average life, when he isn't dropping in uninvited on his big-breasted friend next door. One day, a magical circle appears in his room, revealing Angelia, a princess from another world who offers to "reincarnate" him into the greatest hero that ever lived. This would-be hero's life is about to get a lot less boring and a whole lot more dangerous!