Answer
Wa `alaykum as-salam wa rahmatullahi wa barakatuh.
In the name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
A husband and his wife can practice their normal sexual relation whenever they want, with the exception of sexual intercourse (i.e. genital contact of the male and female sex organs) during menstruation.
Responding to your question, prominent Muslim scholar and Da`iyah Zeinab Mustafa said:
Allah says in the Qur’an: “And they ask you (Muhammad) about menstruation; say, “It is a discomfort.” Therefore, keep aloof from the women during the menstrual discharge and do not go near them until they have become clean] (Al-Baqarah 2:222)
This interdict from Allah applies only to sexual intercourse as described. This has also been clearly established in the authentic Sunnah, as reported in the well-attested hadiths of the Prophet (peace and blessings be upon him).
Islam is a practical and realistic religion. It does not forbid all forms of sexual gratification during menstruation. The only forbidden act at the time of menstruation is sexual intercourse. The Prophet (peace and blessings be upon him) would seek other forms of sexual relation during the period of any his wives’ menses.
Therefore, what you mentioned in your question is allowed as long as no sexual intercourse takes place.
For more, see these fatwas:
Do’s and Don’ts during Your Period in Islam
Why Can’t You Have Sex with Your Wife during Menses?
Sex after Period and before Ghusl in Islam
Allah Almighty knows best.