This is an article written by the author Professor yy. The background is the time of Harry Potter, and the heroine is at the same level as Harry. The relationship between the heroine and Sif develops very slowly (the extra episode will be very sweet and meaty). It must be HD. I really love Sif, but the reason why the relationship develops slowly is that only after Sif has dealt with Lily's feelings can he truly face a new beginning, and he doesn't want to force Sif to fall in love with the heroine midway. That's probably it. The author will do his best to consider Severus, and the heroine will be as real as possible.