The Pillion Rider
Scholars have said that whoever sees themselves as a pillion rider behind a man on a horse in a dream, it may indicate that they will achieve their goal or reach a certain matter with the help of that man, whether in religious or worldly affairs. The pillion rider might be interpreted as a follower or successor to the man riding in front, and perhaps diligently striving for their companion.
Per Ibn Sirin's Muntakhab al-Kalam fi Tafsir al-Ahlam
Note: These are traditional scholarly interpretations (ijtihad) drawn from a specific classical source — not a binding religious ruling, fortune-telling, or a prediction of the future.