At least informing your parents about your own engagement would be the more prudent course of action, a consideration of a normal person.
After all, if you were engaged outside, you definitely couldn't do it without mentioning a word to your parents.
Moreover, it's best for the parents of both parties to meet again to be more secure.
Shen Gu Mirai's parents were not old-fashioned either. Although Beichuan Lin was strict with Beichuan Si and Beichuan Huili, she was quite approachable outside, not to mention Shen Gu Mirai's parents were renowned scholars at the university. Solely in terms of social class, they were considered an upper-middle-class family in Tokyo.
Additionally, since Shen Gu Mirai was smart and capable, Beichuan Lin should logically have no dissatisfaction.
He meant to ask Beichuan Lin roughly when she would return, but since she was planning to come back during the Kyubei Festival on next Wednesday, there was no need for Beichuan Si to inquire further.
