Dreams dictionary: Sucking
Dreams dictionary: Interpretation 1
To dream that you are sucking on something indicates that you need emotional nurturance. You are expressing a desire to escape from your daily responsibilities. Alternatively, the dream refers to low self-esteem and feelings of inferiority. The dream may also be a metaphor for "sucking up" to someone or that you are a "sucker" in some waking situation.
Dreams dictionary: Interpretation 2
To dream that someone is sucking on you suggests that you are feeling drained, physically and/or emotionally. You feel that you are too much of a giver in a situation or relationship.